Hi, Russ I would like the dimensions please also if possible how the loop antenna is wound internally, I will take this to my local fabrication shop so they can make the structural components. After I have the estimate I will pass it back to the group along with contact information for the fab shop so others can build copies. Problem with the 10509's on ebay is the people have them up with BIN's for insane money the last one I saw was in AS-IS condition was $695 I may be crazy but I am not stupid! 73 - Scott N1JIN On Thu, Sep 11, 2008 at 3:13 PM, <wa3frp@aol.com> wrote: > Hi Scott, > > I enjoy your passion for restoring old equipment. BTW, I have a 10509A > here. Let me know if you would like the dimensions. I don't see too many > 10509A around but occasionally one comes up on eBay. While recapping, also > check to see if any reistors look damaged. In my rescent restoration of the > GR Frequency Standard, I replaced a number of carbon resistors that had > changed value over time, most likely from abuse. > > Enjoy! Let me know how I can assist. > > Russ > > > -----Original Message----- > From: Scott McGrath <scmcgrath@gmail.com> > To: wa3frp@aol.com; time-nuts@febo.com > Sent: Thu, 11 Sep 2008 11:32 am > Subject: Re: [time-nuts] Odd HP 117A configuration > > > > Hi Russ, > > Yes i did and it was a marvelous hack in the best sense of the word, > It was fascinating to see how this actually worked, it of course is no > longer necessary and I have removed it in favor of protecting the A1 > assembly fully within the chassis. > > My 117A is a Prefix 438A unit and my manual covers 525A and below. > I'm still debating whether to use a AMRAD antenna and disconnect the > +35 from the antenna (by installing a jumper block for reversability) > or find the proper 10509A loop antenna for authenticity. I have > been offered a amp assembly for the antenna by another member so I > have thought about fabricating the actual loop assembly but I do not > have dimensions for the loop itself which looks to be center tapped > which also would the tube which bisects the loop. > > I bought this a decade ago and was only able to find a manual recently > always kept it because I knew how rare this unit is. Right now it's > been recapped (electrolytics) and I have replaced the chassis mount > transistors BTW a NTE121 will replace the TO-3 pass transistor if that > has given up the ghost. RIght now I am going through the power > supply board A9 and replacing the resistors many of which have changed > value after physically rebuilding the PCB which had a 1/2" hole burned > in the area of R2-4. One of the challenges of recapping is that > electrolytics are now much smaller for equivalent ratings so a lot of > teflon sleeving has been used to prevent potential short circuits. > > So much fun to be had with this stuff! > > - Regards Scott > > On Thu, Sep 11, 2008 at 10:50 AM, <wa3frp@aol.com> wrote: >> >> Scott, >> >> Good luck on the rare 117A. >> >> Did you get my e-mail with attachment containing the pages of the > > manual for >> >> your updated unit? >> >> Russ >> >> -----Original Message----- >> From: Scott McGrath <scmcgrath@gmail.com> >> To: wa3frp@aol.com >> Sent: Wed, 10 Sep 2008 12:42 pm >> Subject: Re: [time-nuts] Odd HP 117A configuration >> >> >> >> Hi, Ross >> >> Please - It would be interesting to see how this worked. From the >> date codes on the components my 117A was built in late 1964 - date >> codes on conversion module date from 1968. As Tom noted it is a >> interesting historical footnote from use of the atomic timescale to >> UTC timescale with leap seconds. And now due to the influence of >> embedded device manfacturers who want 'cheap n cheerful' firmware we >> are now discussing doing away with leap seconds. Interesting how >> the pendulum of historical trends oscillates. >> >> Right now the 117A is having all the electrolytics replaced while I am >> reconstructing the PS module trace by trace >> >> - Scott >> >> >> >> On Wed, Sep 10, 2008 at 7:43 AM, <wa3frp@aol.com> wrote: >>> >>> Scott, >>> I had a chance to look at my HP 117A manual last night and saw that >> >> your >>> >>> configuration is described there. If it is not described in the HP >> >> 117A >>> >>> manual that you have, would you like me to copy those pages and send >> >> them to >>> >>> you as an attachment? >>> Russ >>> >>> >>> -----Original Message----- >>> From: Scott McGrath <scmcgrath@gmail.com> >>> To: time-nuts@febo.com >>> Sent: Mon, 8 Sep 2008 3:50 pm >>> Subject: [time-nuts] Odd HP 117A configuration >>> >>> >>> >>> All, >>> >>> I purchased a 117A at a hamfest years ago and am just now looking > > into >>> >>> it. This 117A is a bit different from the ones in the manual and >>> in pictures up on the web as it incorporates a telechron reduction >>> motor installed in fthe area in front of the TRF module harness >>> connector. Had not looked at this unit much as I did not have a >>> manual which I now have as the power supply board (A9) had a charred >>> hole blown in it. The TRF module does not insert fully into the >>> chassis due to the presence of the clockwork module. Interestingly >>> enough the clockwork looks like HP installed it or someone did a VERY >>> good job. Does anyone know what this clockwork is intended for? >>> >>> I am now rebuidling the circuit board with glass filled epoxy (West >>> Brothers + microsphere filler) with a mold/retaining dam made from >>> silicone rubber. >>> >>> Also back when I was at UNH when I was young and foolish a HP 117A > > was >>> >>> my introduction to precision timing as Jim Williams in Demerrit > > Hall's >>> >>> maintained the frequency standard which consisted of a HP117A and a > > HP >>> >>> 5245M frequency counter along with a decade worth of recorder output. >>> >>> _______________________________________________ >>> 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. >>> >>> >> >> > >