DS
Dave Sublette
Thu, Aug 31, 2017 12:34 PM
Good morning,
I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
Good morning,
I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
BR
Bruce Raymond
Thu, Aug 31, 2017 12:49 PM
Hi Dave,
Thanks for the update. I have a couple of old drills that need new
battery packs. I don't see any problem buying NiMH batteries (I've got
Jack Ma on speed dial ...). How do you handle the charger?
Thanks.
73 Bruce
P.S. We got 5" of rain in south Alabama in the last 24 hours.
Dave Sublette via mvus-list mailto:mvus-list@febo.com
Thursday, August 31, 2017 7:34 AM
Good morning,
I haven’t reported for several days because I either could not hear
the beacon or it was in the noise. This morning it is 15 to 35 dB out
of the noise with QSB between those levels every 10-15 seconds. Looks
like things are stirring in the upper regions. I suspect the hurricane
remnants will do a number on VHF and up propagation this week. We are
due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out of
the noise. Yes, I can see -155 dB. I don’t know what they reference
their dB to. But I recall calibrating the Scale with a sig gen a few
weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly
precise throughout the entire 180 dB range. When I get some time, I
will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for
tools for a friend of mine this week. I removed the Lithium batteries
and replaced them with NIMH AA cells. The old pack were 1300 mah
rating and the new cells are 3500 mah rated. The new packs weigh 1
pound less, each and have almost three times the capacity. Of course I
had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt
LED units that are about an inch in diameter. I found that three of
them would fit in the old head and wired them in series. They only
draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might
consider this sort of a project. I found it very enjoyable. Of course
there were the usual missteps, back up and redos, etc., but those are
quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
mvus-list mailing list
mvus-list@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
Hi Dave,
Thanks for the update. I have a couple of old drills that need new
battery packs. I don't see any problem buying NiMH batteries (I've got
Jack Ma on speed dial ...). How do you handle the charger?
Thanks.
73 Bruce
P.S. We got 5" of rain in south Alabama in the last 24 hours.
> Dave Sublette via mvus-list <mailto:mvus-list@febo.com>
> Thursday, August 31, 2017 7:34 AM
> Good morning,
>
> I haven’t reported for several days because I either could not hear
> the beacon or it was in the noise. This morning it is 15 to 35 dB out
> of the noise with QSB between those levels every 10-15 seconds. Looks
> like things are stirring in the upper regions. I suspect the hurricane
> remnants will do a number on VHF and up propagation this week. We are
> due to get rain here today.
>
> According to my HDSR program -120 dB is S1. That level is 35 dB out of
> the noise. Yes, I can see -155 dB. I don’t know what they reference
> their dB to. But I recall calibrating the Scale with a sig gen a few
> weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly
> precise throughout the entire 180 dB range. When I get some time, I
> will look into it.
>
> I finished rebuilding a couple of Dewalt 36 volt battery packs for
> tools for a friend of mine this week. I removed the Lithium batteries
> and replaced them with NIMH AA cells. The old pack were 1300 mah
> rating and the new cells are 3500 mah rated. The new packs weigh 1
> pound less, each and have almost three times the capacity. Of course I
> had to remake the charger, etc…
>
> Then I converted his work light from bulb to LED. MPJA sells 12 volt
> LED units that are about an inch in diameter. I found that three of
> them would fit in the old head and wired them in series. They only
> draw 100 ma and they really put out the light.
>
> Those of you who might have old tools sets with bad packs might
> consider this sort of a project. I found it very enjoyable. Of course
> there were the usual missteps, back up and redos, etc., but those are
> quickly forgotten.
>
> Stay dry and may the windspeed remain reasonably low.
>
> Dve, K4TO
>
> ps — my new 47 element looper is due to arrive on Friday.
>
> _______________________________________________
> mvus-list mailing list
> mvus-list@febo.com
> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
>
>
DS
Dave Sublette
Thu, Aug 31, 2017 1:10 PM
Good morning Bruce,
The chargers for the Lithium packs are usually complicated, with individual cell voltage monitor circuits and precision regulators. I remove all of that, since it is not necessary for NIMH charging. In my case, I was able to save and use the rectifier and filter from the old circuit. I bought ($7) a surplus transformer with the necessary voltage and installed it in the old case. I kept all of the original connectors intact because the tools involved needed to use that form. For the charging regulator I just put a series power resistor to limit the maximum charging current to 350 mah ( 0.1C). As the cells reach max charge, the charge rate drops.
The old system had indicator lights on it to tell you when the pack was charged, if the pack was too hot, etc. It was also a rapid charger that would bring the pack to full charge in a couple of hours. The revised system has none of that. It is a slow charger. It will take 12-16 hours to charge and you should remove the pack after that. That’s not as useful as the old system. But with double capacity, it’s not the penalty you might think.
To replace the old pack would have been $65. The new batteries were $30. I didn’t charge him anything for labor. It is my entertainment. So — you decide if it is worth it for you. The main thing we gained was that he now has his tools available. They were useless sitting on the bench with batteries to run them. A 36 volt tool system (three tools as I recall) would be expensive to replace. Hopefully, he will get a few more years use from them.
73,
Dave, K4TO
On Aug 31, 2017, at 8:49 AM, Bruce Raymond bruce@raymondtech.net wrote:
Hi Dave,
Thanks for the update. I have a couple of old drills that need new battery packs. I don't see any problem buying NiMH batteries (I've got Jack Ma on speed dial ...). How do you handle the charger?
Thanks.
73 Bruce
P.S. We got 5" of rain in south Alabama in the last 24 hours.
Dave Sublette via mvus-list mailto:mvus-list@febo.com
Thursday, August 31, 2017 7:34 AM
Good morning,
I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
mvus-list mailing list
mvus-list@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
Good morning Bruce,
The chargers for the Lithium packs are usually complicated, with individual cell voltage monitor circuits and precision regulators. I remove all of that, since it is not necessary for NIMH charging. In my case, I was able to save and use the rectifier and filter from the old circuit. I bought ($7) a surplus transformer with the necessary voltage and installed it in the old case. I kept all of the original connectors intact because the tools involved needed to use that form. For the charging regulator I just put a series power resistor to limit the maximum charging current to 350 mah ( 0.1C). As the cells reach max charge, the charge rate drops.
The old system had indicator lights on it to tell you when the pack was charged, if the pack was too hot, etc. It was also a rapid charger that would bring the pack to full charge in a couple of hours. The revised system has none of that. It is a slow charger. It will take 12-16 hours to charge and you should remove the pack after that. That’s not as useful as the old system. But with double capacity, it’s not the penalty you might think.
To replace the old pack would have been $65. The new batteries were $30. I didn’t charge him anything for labor. It is my entertainment. So — you decide if it is worth it for you. The main thing we gained was that he now has his tools available. They were useless sitting on the bench with batteries to run them. A 36 volt tool system (three tools as I recall) would be expensive to replace. Hopefully, he will get a few more years use from them.
73,
Dave, K4TO
> On Aug 31, 2017, at 8:49 AM, Bruce Raymond <bruce@raymondtech.net> wrote:
>
> Hi Dave,
>
> Thanks for the update. I have a couple of old drills that need new battery packs. I don't see any problem buying NiMH batteries (I've got Jack Ma on speed dial ...). How do you handle the charger?
>
> Thanks.
>
> 73 Bruce
>
> P.S. We got 5" of rain in south Alabama in the last 24 hours.
>
>> Dave Sublette via mvus-list <mailto:mvus-list@febo.com>
>> Thursday, August 31, 2017 7:34 AM
>> Good morning,
>>
>> I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
>>
>> According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
>>
>> I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
>>
>> Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
>>
>> Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
>>
>> Stay dry and may the windspeed remain reasonably low.
>>
>> Dve, K4TO
>>
>> ps — my new 47 element looper is due to arrive on Friday.
>>
>> _______________________________________________
>> mvus-list mailing list
>> mvus-list@febo.com
>> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
>>
>>
>
DY
Daun Yeagley
Thu, Aug 31, 2017 1:12 PM
I am a bit confused with the battery comments. Why would you remove
Lithium cells and put in NiMH's?
From the way it reads, I wonder if you swapped the names. Lithium has
a lot more capacity per weight or volume.
I have converted some battery pack from NiCad or NiMH to lithium quite
successfully.
Daun
Daun E. Yeagley, II, N8ASB
On 8/31/2017 8:49 AM, Bruce Raymond via mvus-list wrote:
Hi Dave,
Thanks for the update. I have a couple of old drills that need new
battery packs. I don't see any problem buying NiMH batteries (I've got
Jack Ma on speed dial ...). How do you handle the charger?
Thanks.
73 Bruce
P.S. We got 5" of rain in south Alabama in the last 24 hours.
Dave Sublette via mvus-list mailto:mvus-list@febo.com
Thursday, August 31, 2017 7:34 AM
Good morning,
I haven’t reported for several days because I either could not hear
the beacon or it was in the noise. This morning it is 15 to 35 dB out
of the noise with QSB between those levels every 10-15 seconds. Looks
like things are stirring in the upper regions. I suspect the
hurricane remnants will do a number on VHF and up propagation this
week. We are due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out
of the noise. Yes, I can see -155 dB. I don’t know what they
reference their dB to. But I recall calibrating the Scale with a sig
gen a few weeks ago. I don’t remember what S-9 was, but the SDR is
astoundingly precise throughout the entire 180 dB range. When I get
some time, I will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for
tools for a friend of mine this week. I removed the Lithium batteries
and replaced them with NIMH AA cells. The old pack were 1300 mah
rating and the new cells are 3500 mah rated. The new packs weigh 1
pound less, each and have almost three times the capacity. Of course
I had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt
LED units that are about an inch in diameter. I found that three of
them would fit in the old head and wired them in series. They only
draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might
consider this sort of a project. I found it very enjoyable. Of course
there were the usual missteps, back up and redos, etc., but those are
quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
mvus-list mailing list
mvus-list@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
I am a bit confused with the battery comments. Why would you remove
Lithium cells and put in NiMH's?
From the way it reads, I wonder if you swapped the names. Lithium has
a lot more capacity per weight or volume.
I have converted some battery pack from NiCad or NiMH to lithium quite
successfully.
Daun
Daun E. Yeagley, II, N8ASB
On 8/31/2017 8:49 AM, Bruce Raymond via mvus-list wrote:
> Hi Dave,
>
> Thanks for the update. I have a couple of old drills that need new
> battery packs. I don't see any problem buying NiMH batteries (I've got
> Jack Ma on speed dial ...). How do you handle the charger?
>
> Thanks.
>
> 73 Bruce
>
> P.S. We got 5" of rain in south Alabama in the last 24 hours.
>
>> Dave Sublette via mvus-list <mailto:mvus-list@febo.com>
>> Thursday, August 31, 2017 7:34 AM
>> Good morning,
>>
>> I haven’t reported for several days because I either could not hear
>> the beacon or it was in the noise. This morning it is 15 to 35 dB out
>> of the noise with QSB between those levels every 10-15 seconds. Looks
>> like things are stirring in the upper regions. I suspect the
>> hurricane remnants will do a number on VHF and up propagation this
>> week. We are due to get rain here today.
>>
>> According to my HDSR program -120 dB is S1. That level is 35 dB out
>> of the noise. Yes, I can see -155 dB. I don’t know what they
>> reference their dB to. But I recall calibrating the Scale with a sig
>> gen a few weeks ago. I don’t remember what S-9 was, but the SDR is
>> astoundingly precise throughout the entire 180 dB range. When I get
>> some time, I will look into it.
>>
>> I finished rebuilding a couple of Dewalt 36 volt battery packs for
>> tools for a friend of mine this week. I removed the Lithium batteries
>> and replaced them with NIMH AA cells. The old pack were 1300 mah
>> rating and the new cells are 3500 mah rated. The new packs weigh 1
>> pound less, each and have almost three times the capacity. Of course
>> I had to remake the charger, etc…
>>
>> Then I converted his work light from bulb to LED. MPJA sells 12 volt
>> LED units that are about an inch in diameter. I found that three of
>> them would fit in the old head and wired them in series. They only
>> draw 100 ma and they really put out the light.
>>
>> Those of you who might have old tools sets with bad packs might
>> consider this sort of a project. I found it very enjoyable. Of course
>> there were the usual missteps, back up and redos, etc., but those are
>> quickly forgotten.
>>
>> Stay dry and may the windspeed remain reasonably low.
>>
>> Dve, K4TO
>>
>> ps — my new 47 element looper is due to arrive on Friday.
>>
>> _______________________________________________
>> mvus-list mailing list
>> mvus-list@febo.com
>> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
>>
>>
>
> _______________________________________________
> mvus-list mailing list
> mvus-list@febo.com
> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
BR
Bruce Raymond
Thu, Aug 31, 2017 1:15 PM
HI Dave,
Thanks! Much appreciated.
73 Bruce
Dave Sublette mailto:k4to@arrl.net
Thursday, August 31, 2017 8:10 AM
Good morning Bruce,
The chargers for the Lithium packs are usually complicated, with
individual cell voltage monitor circuits and precision regulators. I
remove all of that, since it is not necessary for NIMH charging. In my
case, I was able to save and use the rectifier and filter from the old
circuit. I bought ($7) a surplus transformer with the necessary
voltage and installed it in the old case. I kept all of the original
connectors intact because the tools involved needed to use that form.
For the charging regulator I just put a series power resistor to limit
the maximum charging current to 350 mah ( 0.1C). As the cells reach
max charge, the charge rate drops.
The old system had indicator lights on it to tell you when the pack
was charged, if the pack was too hot, etc. It was also a rapid charger
that would bring the pack to full charge in a couple of hours. The
revised system has none of that. It is a slow charger. It will take
12-16 hours to charge and you should remove the pack after that.
That’s not as useful as the old system. But with double capacity, it’s
not the penalty you might think.
To replace the old pack would have been $65. The new batteries were
$30. I didn’t charge him anything for labor. It is my entertainment.
So — you decide if it is worth it for you. The main thing we gained
was that he now has his tools available. They were useless sitting on
the bench with batteries to run them. A 36 volt tool system (three
tools as I recall) would be expensive to replace. Hopefully, he will
get a few more years use from them.
73,
Dave, K4TO
Bruce Raymond mailto:bruce@raymondtech.net
Thursday, August 31, 2017 7:49 AM
Hi Dave,
Thanks for the update. I have a couple of old drills that need new
battery packs. I don't see any problem buying NiMH batteries (I've got
Jack Ma on speed dial ...). How do you handle the charger?
Thanks.
73 Bruce
P.S. We got 5" of rain in south Alabama in the last 24 hours.
Dave Sublette via mvus-list mailto:mvus-list@febo.com
Thursday, August 31, 2017 7:34 AM
Good morning,
I haven’t reported for several days because I either could not hear
the beacon or it was in the noise. This morning it is 15 to 35 dB out
of the noise with QSB between those levels every 10-15 seconds. Looks
like things are stirring in the upper regions. I suspect the hurricane
remnants will do a number on VHF and up propagation this week. We are
due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out of
the noise. Yes, I can see -155 dB. I don’t know what they reference
their dB to. But I recall calibrating the Scale with a sig gen a few
weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly
precise throughout the entire 180 dB range. When I get some time, I
will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for
tools for a friend of mine this week. I removed the Lithium batteries
and replaced them with NIMH AA cells. The old pack were 1300 mah
rating and the new cells are 3500 mah rated. The new packs weigh 1
pound less, each and have almost three times the capacity. Of course I
had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt
LED units that are about an inch in diameter. I found that three of
them would fit in the old head and wired them in series. They only
draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might
consider this sort of a project. I found it very enjoyable. Of course
there were the usual missteps, back up and redos, etc., but those are
quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
mvus-list mailing list
mvus-list@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
HI Dave,
Thanks! Much appreciated.
73 Bruce
> Dave Sublette <mailto:k4to@arrl.net>
> Thursday, August 31, 2017 8:10 AM
> Good morning Bruce,
>
> The chargers for the Lithium packs are usually complicated, with
> individual cell voltage monitor circuits and precision regulators. I
> remove all of that, since it is not necessary for NIMH charging. In my
> case, I was able to save and use the rectifier and filter from the old
> circuit. I bought ($7) a surplus transformer with the necessary
> voltage and installed it in the old case. I kept all of the original
> connectors intact because the tools involved needed to use that form.
> For the charging regulator I just put a series power resistor to limit
> the maximum charging current to 350 mah ( 0.1C). As the cells reach
> max charge, the charge rate drops.
>
> The old system had indicator lights on it to tell you when the pack
> was charged, if the pack was too hot, etc. It was also a rapid charger
> that would bring the pack to full charge in a couple of hours. The
> revised system has none of that. It is a slow charger. It will take
> 12-16 hours to charge and you should remove the pack after that.
> That’s not as useful as the old system. But with double capacity, it’s
> not the penalty you might think.
>
> To replace the old pack would have been $65. The new batteries were
> $30. I didn’t charge him anything for labor. It is my entertainment.
> So — you decide if it is worth it for you. The main thing we gained
> was that he now has his tools available. They were useless sitting on
> the bench with batteries to run them. A 36 volt tool system (three
> tools as I recall) would be expensive to replace. Hopefully, he will
> get a few more years use from them.
>
> 73,
>
> Dave, K4TO
>
>
>
> Bruce Raymond <mailto:bruce@raymondtech.net>
> Thursday, August 31, 2017 7:49 AM
> Hi Dave,
>
> Thanks for the update. I have a couple of old drills that need new
> battery packs. I don't see any problem buying NiMH batteries (I've got
> Jack Ma on speed dial ...). How do you handle the charger?
>
> Thanks.
>
> 73 Bruce
>
> P.S. We got 5" of rain in south Alabama in the last 24 hours.
>
>
> Dave Sublette via mvus-list <mailto:mvus-list@febo.com>
> Thursday, August 31, 2017 7:34 AM
> Good morning,
>
> I haven’t reported for several days because I either could not hear
> the beacon or it was in the noise. This morning it is 15 to 35 dB out
> of the noise with QSB between those levels every 10-15 seconds. Looks
> like things are stirring in the upper regions. I suspect the hurricane
> remnants will do a number on VHF and up propagation this week. We are
> due to get rain here today.
>
> According to my HDSR program -120 dB is S1. That level is 35 dB out of
> the noise. Yes, I can see -155 dB. I don’t know what they reference
> their dB to. But I recall calibrating the Scale with a sig gen a few
> weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly
> precise throughout the entire 180 dB range. When I get some time, I
> will look into it.
>
> I finished rebuilding a couple of Dewalt 36 volt battery packs for
> tools for a friend of mine this week. I removed the Lithium batteries
> and replaced them with NIMH AA cells. The old pack were 1300 mah
> rating and the new cells are 3500 mah rated. The new packs weigh 1
> pound less, each and have almost three times the capacity. Of course I
> had to remake the charger, etc…
>
> Then I converted his work light from bulb to LED. MPJA sells 12 volt
> LED units that are about an inch in diameter. I found that three of
> them would fit in the old head and wired them in series. They only
> draw 100 ma and they really put out the light.
>
> Those of you who might have old tools sets with bad packs might
> consider this sort of a project. I found it very enjoyable. Of course
> there were the usual missteps, back up and redos, etc., but those are
> quickly forgotten.
>
> Stay dry and may the windspeed remain reasonably low.
>
> Dve, K4TO
>
> ps — my new 47 element looper is due to arrive on Friday.
>
> _______________________________________________
> mvus-list mailing list
> mvus-list@febo.com
> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
>
>
DS
Dave Sublette
Thu, Aug 31, 2017 2:14 PM
Daun,
The lithium packs were old and would no longer hold a charge. They were old technology. To replace them with newer cells would have called for a rework of the charger anyway. New “factory replacement” packs were prohibitively expensive. The new AA cell, NIMH have a 3500 Mah rating — twice what the old Lithium cells had. The new packs weigh one pound less than the old lithium and have twice the capacity. They cost half of what a replacement pack would have been. I used the old battery enclosure and connector so the tools would fit.
I hope this clears up why we did it.
Dave, K4TO
On Aug 31, 2017, at 9:15 AM, Bruce Raymond bruce@raymondtech.net wrote:
HI Dave,
Thanks! Much appreciated.
73 Bruce
Dave Sublette <mailto:k4to@arrl.net mailto:k4to@arrl.net>
Thursday, August 31, 2017 8:10 AM
Good morning Bruce,
The chargers for the Lithium packs are usually complicated, with individual cell voltage monitor circuits and precision regulators. I remove all of that, since it is not necessary for NIMH charging. In my case, I was able to save and use the rectifier and filter from the old circuit. I bought ($7) a surplus transformer with the necessary voltage and installed it in the old case. I kept all of the original connectors intact because the tools involved needed to use that form. For the charging regulator I just put a series power resistor to limit the maximum charging current to 350 mah ( 0.1C). As the cells reach max charge, the charge rate drops.
The old system had indicator lights on it to tell you when the pack was charged, if the pack was too hot, etc. It was also a rapid charger that would bring the pack to full charge in a couple of hours. The revised system has none of that. It is a slow charger. It will take 12-16 hours to charge and you should remove the pack after that. That’s not as useful as the old system. But with double capacity, it’s not the penalty you might think.
To replace the old pack would have been $65. The new batteries were $30. I didn’t charge him anything for labor. It is my entertainment. So — you decide if it is worth it for you. The main thing we gained was that he now has his tools available. They were useless sitting on the bench with batteries to run them. A 36 volt tool system (three tools as I recall) would be expensive to replace. Hopefully, he will get a few more years use from them.
73,
Dave, K4TO
Bruce Raymond <mailto:bruce@raymondtech.net mailto:bruce@raymondtech.net>
Thursday, August 31, 2017 7:49 AM
Hi Dave,
Thanks for the update. I have a couple of old drills that need new battery packs. I don't see any problem buying NiMH batteries (I've got Jack Ma on speed dial ...). How do you handle the charger?
Thanks.
73 Bruce
P.S. We got 5" of rain in south Alabama in the last 24 hours.
Dave Sublette via mvus-list mailto:mvus-list@febo.com
Thursday, August 31, 2017 7:34 AM
Good morning,
I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
mvus-list mailing list
mvus-list@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
Daun,
The lithium packs were old and would no longer hold a charge. They were old technology. To replace them with newer cells would have called for a rework of the charger anyway. New “factory replacement” packs were prohibitively expensive. The new AA cell, NIMH have a 3500 Mah rating — twice what the old Lithium cells had. The new packs weigh one pound less than the old lithium and have twice the capacity. They cost half of what a replacement pack would have been. I used the old battery enclosure and connector so the tools would fit.
I hope this clears up why we did it.
Dave, K4TO
> On Aug 31, 2017, at 9:15 AM, Bruce Raymond <bruce@raymondtech.net> wrote:
>
> HI Dave,
>
> Thanks! Much appreciated.
>
> 73 Bruce
>
>> Dave Sublette <mailto:k4to@arrl.net <mailto:k4to@arrl.net>>
>> Thursday, August 31, 2017 8:10 AM
>> Good morning Bruce,
>>
>> The chargers for the Lithium packs are usually complicated, with individual cell voltage monitor circuits and precision regulators. I remove all of that, since it is not necessary for NIMH charging. In my case, I was able to save and use the rectifier and filter from the old circuit. I bought ($7) a surplus transformer with the necessary voltage and installed it in the old case. I kept all of the original connectors intact because the tools involved needed to use that form. For the charging regulator I just put a series power resistor to limit the maximum charging current to 350 mah ( 0.1C). As the cells reach max charge, the charge rate drops.
>>
>> The old system had indicator lights on it to tell you when the pack was charged, if the pack was too hot, etc. It was also a rapid charger that would bring the pack to full charge in a couple of hours. The revised system has none of that. It is a slow charger. It will take 12-16 hours to charge and you should remove the pack after that. That’s not as useful as the old system. But with double capacity, it’s not the penalty you might think.
>>
>> To replace the old pack would have been $65. The new batteries were $30. I didn’t charge him anything for labor. It is my entertainment. So — you decide if it is worth it for you. The main thing we gained was that he now has his tools available. They were useless sitting on the bench with batteries to run them. A 36 volt tool system (three tools as I recall) would be expensive to replace. Hopefully, he will get a few more years use from them.
>>
>> 73,
>>
>> Dave, K4TO
>>
>>
>>
>> Bruce Raymond <mailto:bruce@raymondtech.net <mailto:bruce@raymondtech.net>>
>> Thursday, August 31, 2017 7:49 AM
>> Hi Dave,
>>
>> Thanks for the update. I have a couple of old drills that need new battery packs. I don't see any problem buying NiMH batteries (I've got Jack Ma on speed dial ...). How do you handle the charger?
>>
>> Thanks.
>>
>> 73 Bruce
>>
>> P.S. We got 5" of rain in south Alabama in the last 24 hours.
>>
>>
>> Dave Sublette via mvus-list <mailto:mvus-list@febo.com>
>> Thursday, August 31, 2017 7:34 AM
>> Good morning,
>>
>> I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
>>
>> According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
>>
>> I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
>>
>> Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
>>
>> Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
>>
>> Stay dry and may the windspeed remain reasonably low.
>>
>> Dve, K4TO
>>
>> ps — my new 47 element looper is due to arrive on Friday.
>>
>> _______________________________________________
>> mvus-list mailing list
>> mvus-list@febo.com
>> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
DY
Daun Yeagley
Thu, Aug 31, 2017 2:34 PM
Hi Dave
I just saw your explanation to Bruce too. Seems unusual though, but it
would be good to update from the older cells. I've done conversions
with newer cells, and that seems to work well. One thing on Lithium's
is that if you are using multiple cells (like you are), you really need
to use a balance charger, which of course is a lot more complicated than
the NiMH type chargers.
I'm still puzzled though that your Lithium's are heavier than the NiMH's.
Daun
Daun E. Yeagley, II, N8ASB
On 8/31/2017 10:14 AM, Dave Sublette via mvus-list wrote:
Daun,
The lithium packs were old and would no longer hold a charge. They were old technology. To replace them with newer cells would have called for a rework of the charger anyway. New “factory replacement” packs were prohibitively expensive. The new AA cell, NIMH have a 3500 Mah rating — twice what the old Lithium cells had. The new packs weigh one pound less than the old lithium and have twice the capacity. They cost half of what a replacement pack would have been. I used the old battery enclosure and connector so the tools would fit.
I hope this clears up why we did it.
Dave, K4TO
On Aug 31, 2017, at 9:15 AM, Bruce Raymond bruce@raymondtech.net wrote:
HI Dave,
Thanks! Much appreciated.
73 Bruce
Dave Sublette <mailto:k4to@arrl.net mailto:k4to@arrl.net>
Thursday, August 31, 2017 8:10 AM
Good morning Bruce,
The chargers for the Lithium packs are usually complicated, with individual cell voltage monitor circuits and precision regulators. I remove all of that, since it is not necessary for NIMH charging. In my case, I was able to save and use the rectifier and filter from the old circuit. I bought ($7) a surplus transformer with the necessary voltage and installed it in the old case. I kept all of the original connectors intact because the tools involved needed to use that form. For the charging regulator I just put a series power resistor to limit the maximum charging current to 350 mah ( 0.1C). As the cells reach max charge, the charge rate drops.
The old system had indicator lights on it to tell you when the pack was charged, if the pack was too hot, etc. It was also a rapid charger that would bring the pack to full charge in a couple of hours. The revised system has none of that. It is a slow charger. It will take 12-16 hours to charge and you should remove the pack after that. That’s not as useful as the old system. But with double capacity, it’s not the penalty you might think.
To replace the old pack would have been $65. The new batteries were $30. I didn’t charge him anything for labor. It is my entertainment. So — you decide if it is worth it for you. The main thing we gained was that he now has his tools available. They were useless sitting on the bench with batteries to run them. A 36 volt tool system (three tools as I recall) would be expensive to replace. Hopefully, he will get a few more years use from them.
73,
Dave, K4TO
Bruce Raymond <mailto:bruce@raymondtech.net mailto:bruce@raymondtech.net>
Thursday, August 31, 2017 7:49 AM
Hi Dave,
Thanks for the update. I have a couple of old drills that need new battery packs. I don't see any problem buying NiMH batteries (I've got Jack Ma on speed dial ...). How do you handle the charger?
Thanks.
73 Bruce
P.S. We got 5" of rain in south Alabama in the last 24 hours.
Dave Sublette via mvus-list mailto:mvus-list@febo.com
Thursday, August 31, 2017 7:34 AM
Good morning,
I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
Stay dry and may the windspeed remain reasonably low.
Dve, K4TO
ps — my new 47 element looper is due to arrive on Friday.
mvus-list mailing list
mvus-list@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
Hi Dave
I just saw your explanation to Bruce too. Seems unusual though, but it
would be good to update from the older cells. I've done conversions
with newer cells, and that seems to work well. One thing on Lithium's
is that if you are using multiple cells (like you are), you really need
to use a balance charger, which of course is a lot more complicated than
the NiMH type chargers.
I'm still puzzled though that your Lithium's are heavier than the NiMH's.
Daun
Daun E. Yeagley, II, N8ASB
On 8/31/2017 10:14 AM, Dave Sublette via mvus-list wrote:
> Daun,
>
> The lithium packs were old and would no longer hold a charge. They were old technology. To replace them with newer cells would have called for a rework of the charger anyway. New “factory replacement” packs were prohibitively expensive. The new AA cell, NIMH have a 3500 Mah rating — twice what the old Lithium cells had. The new packs weigh one pound less than the old lithium and have twice the capacity. They cost half of what a replacement pack would have been. I used the old battery enclosure and connector so the tools would fit.
>
> I hope this clears up why we did it.
>
> Dave, K4TO
>> On Aug 31, 2017, at 9:15 AM, Bruce Raymond <bruce@raymondtech.net> wrote:
>>
>> HI Dave,
>>
>> Thanks! Much appreciated.
>>
>> 73 Bruce
>>
>>> Dave Sublette <mailto:k4to@arrl.net <mailto:k4to@arrl.net>>
>>> Thursday, August 31, 2017 8:10 AM
>>> Good morning Bruce,
>>>
>>> The chargers for the Lithium packs are usually complicated, with individual cell voltage monitor circuits and precision regulators. I remove all of that, since it is not necessary for NIMH charging. In my case, I was able to save and use the rectifier and filter from the old circuit. I bought ($7) a surplus transformer with the necessary voltage and installed it in the old case. I kept all of the original connectors intact because the tools involved needed to use that form. For the charging regulator I just put a series power resistor to limit the maximum charging current to 350 mah ( 0.1C). As the cells reach max charge, the charge rate drops.
>>>
>>> The old system had indicator lights on it to tell you when the pack was charged, if the pack was too hot, etc. It was also a rapid charger that would bring the pack to full charge in a couple of hours. The revised system has none of that. It is a slow charger. It will take 12-16 hours to charge and you should remove the pack after that. That’s not as useful as the old system. But with double capacity, it’s not the penalty you might think.
>>>
>>> To replace the old pack would have been $65. The new batteries were $30. I didn’t charge him anything for labor. It is my entertainment. So — you decide if it is worth it for you. The main thing we gained was that he now has his tools available. They were useless sitting on the bench with batteries to run them. A 36 volt tool system (three tools as I recall) would be expensive to replace. Hopefully, he will get a few more years use from them.
>>>
>>> 73,
>>>
>>> Dave, K4TO
>>>
>>>
>>>
>>> Bruce Raymond <mailto:bruce@raymondtech.net <mailto:bruce@raymondtech.net>>
>>> Thursday, August 31, 2017 7:49 AM
>>> Hi Dave,
>>>
>>> Thanks for the update. I have a couple of old drills that need new battery packs. I don't see any problem buying NiMH batteries (I've got Jack Ma on speed dial ...). How do you handle the charger?
>>>
>>> Thanks.
>>>
>>> 73 Bruce
>>>
>>> P.S. We got 5" of rain in south Alabama in the last 24 hours.
>>>
>>>
>>> Dave Sublette via mvus-list <mailto:mvus-list@febo.com>
>>> Thursday, August 31, 2017 7:34 AM
>>> Good morning,
>>>
>>> I haven’t reported for several days because I either could not hear the beacon or it was in the noise. This morning it is 15 to 35 dB out of the noise with QSB between those levels every 10-15 seconds. Looks like things are stirring in the upper regions. I suspect the hurricane remnants will do a number on VHF and up propagation this week. We are due to get rain here today.
>>>
>>> According to my HDSR program -120 dB is S1. That level is 35 dB out of the noise. Yes, I can see -155 dB. I don’t know what they reference their dB to. But I recall calibrating the Scale with a sig gen a few weeks ago. I don’t remember what S-9 was, but the SDR is astoundingly precise throughout the entire 180 dB range. When I get some time, I will look into it.
>>>
>>> I finished rebuilding a couple of Dewalt 36 volt battery packs for tools for a friend of mine this week. I removed the Lithium batteries and replaced them with NIMH AA cells. The old pack were 1300 mah rating and the new cells are 3500 mah rated. The new packs weigh 1 pound less, each and have almost three times the capacity. Of course I had to remake the charger, etc…
>>>
>>> Then I converted his work light from bulb to LED. MPJA sells 12 volt LED units that are about an inch in diameter. I found that three of them would fit in the old head and wired them in series. They only draw 100 ma and they really put out the light.
>>>
>>> Those of you who might have old tools sets with bad packs might consider this sort of a project. I found it very enjoyable. Of course there were the usual missteps, back up and redos, etc., but those are quickly forgotten.
>>>
>>> Stay dry and may the windspeed remain reasonably low.
>>>
>>> Dve, K4TO
>>>
>>> ps — my new 47 element looper is due to arrive on Friday.
>>>
>>> _______________________________________________
>>> mvus-list mailing list
>>> mvus-list@febo.com
>>> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
> _______________________________________________
> mvus-list mailing list
> mvus-list@febo.com
> https://www.febo.com/cgi-bin/mailman/listinfo/mvus-list
