Last year, I posted a message on timenuts about a project for an internal
prescaler board for the 53131A (and related 53181A & 53132A) counter.

I successfully cloned the original 3 GHz board from Agilent and I've looked
further. I then designed a more advanced prescaler PCB based on the Analog
ADF4107 PLL, able to reach 6 GHz and beyond. I worked on component selection
to get a stable board and I'm now in the final stages of the design process.

I will order soon a batch of the final PCB and consider selling them to
recover some of the bucks I spend on the project. My goal is NOT to make big
money, just help some ham and others measurements addicted like me to
benefit from a frequency extensions for one of the more wide-spread counter.
This said, I need your opinion about some points.

1- The minimum measurable frequency for that design is 80-85 MHz for a sine
wave (down to DC with a square wave). To get lower specs, I need to add some
more components to get fast-rising edge in all cases at the input of the
ADF4107. I don't think there is a need for that as the original 5 GHz board
for Agilent is rated to 200 MHz min. What's your thought ?

2- About sensibility, my goal is to achieve -20 dB over the 0.1-6 GHz range
(as "rated" spec). To get higher sensitivity, I need to add some RF amps. It
would cost more and seems overkill for that application, but .... ?

3- Let's speak about input protection. More protected = less sensitivity.
Right now, the front stage is protected by a voltage limiter (2x dual RF
diode) but it will not support a huge peak (more than 30 dBm). Should I add
some more protection ? In all case, the "rated" spec will be 10 dBm.

4- Connectors. The PCB board will input into a standard SMA connector. I
first planned to provide the board with a short SMA/Type-N cable to mount
inside the 53131A. This is not possible because the front-panel hole is not
big enough and will require hardware mod to fit a Type-N connector. So, the
only other option is a TNC connector at input. Is it a right choice ? A BNC
@ 6+ GHz seems not a good idea, but works just fine too and is the industry
standard...

5- I'm thinking about selling the prescaler board as a "nude" PCB or an
assembled board. Should I sell a "kit" PCB too ? The board is all SMD and
the main chip is a fine pitch TSSOP quite hard to solder. This is not for
beginners.

6- Price. Last but not least : the price ! Right now, the original 3 GHz
board costs $1100 and up to $2200 for the 5 GHz. What a ripoff ! You could
buy some refurbished 3 GHz board on eBay for about $200.

Thanks for your answers !

PS : Two pictures of the Beta 0.7 PCB measuring a 3 GHz / -30 dB signal
(http://cpc.cx/OB) and a 8 GHz / 0 dB signal (http://cpc.cx/OA)

PS2 : Sorry for my bad English.

Samuel DEMEULEMEESTER
Presse Non Stop - Canard PC
http://www.canardpc.com
Tel : +33.6.13.73.4003
MSN : sam@x86.fr

Damn, I forgot to finish the "Price" point.

So, what seems to be a "fair" price ? My goal is €49 for a PCB, €99 for a kit and €149 for an assembled/tested board. It's just a first estimation of what seems fair for me. I still need to check the real price of components and the price will change with the number of buyers, of course.

Samuel DEMEULEMEESTER
Presse Non Stop - Canard PC
http://www.canardpc.com
Tel : +33.6.13.73.4003
MSN : sam@x86.fr

-----Message d'origine-----
De : time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] De la part de Samuel DEMEULEMEESTER
Envoyé : jeudi 25 mars 2010 16:35
À : 'Discussion of precise time and frequency measurement'
Objet : [time-nuts] Low-Cost 6+ GHz Prescaler board for HP/Agilent 53181A/53131A/53132A

Last year, I posted a message on timenuts about a project for an internal
prescaler board for the 53131A (and related 53181A & 53132A) counter.

I successfully cloned the original 3 GHz board from Agilent and I've looked
further. I then designed a more advanced prescaler PCB based on the Analog
ADF4107 PLL, able to reach 6 GHz and beyond. I worked on component selection
to get a stable board and I'm now in the final stages of the design process.

I will order soon a batch of the final PCB and consider selling them to
recover some of the bucks I spend on the project. My goal is NOT to make big
money, just help some ham and others measurements addicted like me to
benefit from a frequency extensions for one of the more wide-spread counter.
This said, I need your opinion about some points.

1- The minimum measurable frequency for that design is 80-85 MHz for a sine
wave (down to DC with a square wave). To get lower specs, I need to add some
more components to get fast-rising edge in all cases at the input of the
ADF4107. I don't think there is a need for that as the original 5 GHz board
for Agilent is rated to 200 MHz min. What's your thought ?

2- About sensibility, my goal is to achieve -20 dB over the 0.1-6 GHz range
(as "rated" spec). To get higher sensitivity, I need to add some RF amps. It
would cost more and seems overkill for that application, but .... ?

3- Let's speak about input protection. More protected = less sensitivity.
Right now, the front stage is protected by a voltage limiter (2x dual RF
diode) but it will not support a huge peak (more than 30 dBm). Should I add
some more protection ? In all case, the "rated" spec will be 10 dBm.

4- Connectors. The PCB board will input into a standard SMA connector. I
first planned to provide the board with a short SMA/Type-N cable to mount
inside the 53131A. This is not possible because the front-panel hole is not
big enough and will require hardware mod to fit a Type-N connector. So, the
only other option is a TNC connector at input. Is it a right choice ? A BNC
@ 6+ GHz seems not a good idea, but works just fine too and is the industry
standard...

5- I'm thinking about selling the prescaler board as a "nude" PCB or an
assembled board. Should I sell a "kit" PCB too ? The board is all SMD and
the main chip is a fine pitch TSSOP quite hard to solder. This is not for
beginners.

6- Price. Last but not least : the price ! Right now, the original 3 GHz
board costs $1100 and up to $2200 for the 5 GHz. What a ripoff ! You could
buy some refurbished 3 GHz board on eBay for about $200.

Thanks for your answers !

PS : Two pictures of the Beta 0.7 PCB measuring a 3 GHz / -30 dB signal
(http://cpc.cx/OB) and a 8 GHz / 0 dB signal (http://cpc.cx/OA)

PS2 : Sorry for my bad English.

Samuel DEMEULEMEESTER
Presse Non Stop - Canard PC
http://www.canardpc.com
Tel : +33.6.13.73.4003
MSN : sam@x86.fr

time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

Hi

I don't need a board so take this as a comment from a "non customer".

Mounting the board inside the counter is a very useful thing. I would go
with the connector that originally was on the front panel. That makes it
mechanically sound and it should work every bit as well as the original.
Second choice would be to lash an SMA into the same location with enough
mechanical support to be very secure. What ever connector is there, it's
going to get a lot of use / abuse.

I do agree that BNC would not be my first choice (or even in the top 10) for
a multi GHz connector in terms of RF performance. It does have the great
virtue of being quick on / quick off.

The levels sound pretty good. I would make sure that the input will take +20
dbm on a continuous basis. It probably should read accurately to +13 dbm. I
would not add a bunch of amplification. Often when you do, it improves
sensitivity, but they do odd things as you overload them.

Low end frequency sounds plenty good enough. There's a fine input just below
it on the counter if you want to go below 100 MHz. I would probably scale
the input caps so that they start to block RF below something like 50 MHz.
That will help with overload and possibly improve sensitivity in real
applications.

Hope that helps.

Bob

-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Samuel DEMEULEMEESTER
Sent: Thursday, March 25, 2010 11:35 AM
To: 'Discussion of precise time and frequency measurement'
Subject: [time-nuts] Low-Cost 6+ GHz Prescaler board for
HP/Agilent53181A/53131A/53132A

Last year, I posted a message on timenuts about a project for an internal
prescaler board for the 53131A (and related 53181A & 53132A) counter.

I successfully cloned the original 3 GHz board from Agilent and I've looked
further. I then designed a more advanced prescaler PCB based on the Analog
ADF4107 PLL, able to reach 6 GHz and beyond. I worked on component selection
to get a stable board and I'm now in the final stages of the design process.

I will order soon a batch of the final PCB and consider selling them to
recover some of the bucks I spend on the project. My goal is NOT to make big
money, just help some ham and others measurements addicted like me to
benefit from a frequency extensions for one of the more wide-spread counter.
This said, I need your opinion about some points.

1- The minimum measurable frequency for that design is 80-85 MHz for a sine
wave (down to DC with a square wave). To get lower specs, I need to add some
more components to get fast-rising edge in all cases at the input of the
ADF4107. I don't think there is a need for that as the original 5 GHz board
for Agilent is rated to 200 MHz min. What's your thought ?

2- About sensibility, my goal is to achieve -20 dB over the 0.1-6 GHz range
(as "rated" spec). To get higher sensitivity, I need to add some RF amps. It
would cost more and seems overkill for that application, but .... ?

3- Let's speak about input protection. More protected = less sensitivity.
Right now, the front stage is protected by a voltage limiter (2x dual RF
diode) but it will not support a huge peak (more than 30 dBm). Should I add
some more protection ? In all case, the "rated" spec will be 10 dBm.

4- Connectors. The PCB board will input into a standard SMA connector. I
first planned to provide the board with a short SMA/Type-N cable to mount
inside the 53131A. This is not possible because the front-panel hole is not
big enough and will require hardware mod to fit a Type-N connector. So, the
only other option is a TNC connector at input. Is it a right choice ? A BNC
@ 6+ GHz seems not a good idea, but works just fine too and is the industry
standard...

5- I'm thinking about selling the prescaler board as a "nude" PCB or an
assembled board. Should I sell a "kit" PCB too ? The board is all SMD and
the main chip is a fine pitch TSSOP quite hard to solder. This is not for
beginners.

6- Price. Last but not least : the price ! Right now, the original 3 GHz
board costs $1100 and up to $2200 for the 5 GHz. What a ripoff ! You could
buy some refurbished 3 GHz board on eBay for about $200.

Thanks for your answers !

PS : Two pictures of the Beta 0.7 PCB measuring a 3 GHz / -30 dB signal
(http://cpc.cx/OB) and a 8 GHz / 0 dB signal (http://cpc.cx/OA)

PS2 : Sorry for my bad English.

Samuel DEMEULEMEESTER
Presse Non Stop - Canard PC
http://www.canardpc.com
Tel : +33.6.13.73.4003
MSN : sam@x86.fr

time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

I'm thinking about the need for a MMIC amplifier before the ADF4107.
I was unable to find a cheap DC-8 GHz GaAs amplifier to put there for a try.

-----Message d'origine-----
De : time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] De la
part de Bob Camp
Envoyé : jeudi 25 mars 2010 17:36
À : 'Discussion of precise time and frequency measurement'
Objet : Re: [time-nuts] Low-Cost 6+ GHz Prescaler board for
HP/Agilent53181A/53131A/53132A

Hi

I don't need a board so take this as a comment from a "non customer".

Mounting the board inside the counter is a very useful thing. I would go
with the connector that originally was on the front panel. That makes it
mechanically sound and it should work every bit as well as the original.
Second choice would be to lash an SMA into the same location with enough
mechanical support to be very secure. What ever connector is there, it's
going to get a lot of use / abuse.

I do agree that BNC would not be my first choice (or even in the top 10) for
a multi GHz connector in terms of RF performance. It does have the great
virtue of being quick on / quick off.

The levels sound pretty good. I would make sure that the input will take +20
dbm on a continuous basis. It probably should read accurately to +13 dbm. I
would not add a bunch of amplification. Often when you do, it improves
sensitivity, but they do odd things as you overload them.

Low end frequency sounds plenty good enough. There's a fine input just below
it on the counter if you want to go below 100 MHz. I would probably scale
the input caps so that they start to block RF below something like 50 MHz.
That will help with overload and possibly improve sensitivity in real
applications.

Hope that helps.

Bob

-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Samuel DEMEULEMEESTER
Sent: Thursday, March 25, 2010 11:35 AM
To: 'Discussion of precise time and frequency measurement'
Subject: [time-nuts] Low-Cost 6+ GHz Prescaler board for
HP/Agilent53181A/53131A/53132A

Last year, I posted a message on timenuts about a project for an internal
prescaler board for the 53131A (and related 53181A & 53132A) counter.

I successfully cloned the original 3 GHz board from Agilent and I've looked
further. I then designed a more advanced prescaler PCB based on the Analog
ADF4107 PLL, able to reach 6 GHz and beyond. I worked on component selection
to get a stable board and I'm now in the final stages of the design process.

I will order soon a batch of the final PCB and consider selling them to
recover some of the bucks I spend on the project. My goal is NOT to make big
money, just help some ham and others measurements addicted like me to
benefit from a frequency extensions for one of the more wide-spread counter.
This said, I need your opinion about some points.

1- The minimum measurable frequency for that design is 80-85 MHz for a sine
wave (down to DC with a square wave). To get lower specs, I need to add some
more components to get fast-rising edge in all cases at the input of the
ADF4107. I don't think there is a need for that as the original 5 GHz board
for Agilent is rated to 200 MHz min. What's your thought ?

2- About sensibility, my goal is to achieve -20 dB over the 0.1-6 GHz range
(as "rated" spec). To get higher sensitivity, I need to add some RF amps. It
would cost more and seems overkill for that application, but .... ?

3- Let's speak about input protection. More protected = less sensitivity.
Right now, the front stage is protected by a voltage limiter (2x dual RF
diode) but it will not support a huge peak (more than 30 dBm). Should I add
some more protection ? In all case, the "rated" spec will be 10 dBm.

4- Connectors. The PCB board will input into a standard SMA connector. I
first planned to provide the board with a short SMA/Type-N cable to mount
inside the 53131A. This is not possible because the front-panel hole is not
big enough and will require hardware mod to fit a Type-N connector. So, the
only other option is a TNC connector at input. Is it a right choice ? A BNC
@ 6+ GHz seems not a good idea, but works just fine too and is the industry
standard...

5- I'm thinking about selling the prescaler board as a "nude" PCB or an
assembled board. Should I sell a "kit" PCB too ? The board is all SMD and
the main chip is a fine pitch TSSOP quite hard to solder. This is not for
beginners.

6- Price. Last but not least : the price ! Right now, the original 3 GHz
board costs $1100 and up to $2200 for the 5 GHz. What a ripoff ! You could
buy some refurbished 3 GHz board on eBay for about $200.

Thanks for your answers !

PS : Two pictures of the Beta 0.7 PCB measuring a 3 GHz / -30 dB signal
(http://cpc.cx/OB) and a 8 GHz / 0 dB signal (http://cpc.cx/OA)

PS2 : Sorry for my bad English.

Samuel DEMEULEMEESTER
Presse Non Stop - Canard PC
http://www.canardpc.com
Tel : +33.6.13.73.4003
MSN : sam@x86.fr

time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.