[time-nuts] WWVB fully converts to new format

anyone have a kluge to allow my vintage HP 117A to continue working? 73 Russ - WA3FRP wa3...@aol.com ___ 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

Re: [time-nuts] General Radio

-nuts@febo.com" Subject: [time-nuts] General Radio Message-ID: Content-Type: text/plain; charset=us-ascii Any schematics for the following general radio Primary standard syncrometer clock Girard 617 417 1766 jsimon1026 @aol.com 691c 690d 694c 696c 698a 692b Sent from my iPhone Russ -

Re: [time-nuts] Description - GR 1120-AB Frequency Standard

ifications that I am currently making to the inner oven. Thanks to everyone on the list for their advice and assistance. Russ WA3FRP -Original Message- From: Jim Hall <[EMAIL PROTECTED]> To: Discussion of precise time and frequency measurement Sent: Wed, 3 Sep 2008 10:06 pm Subje

Re: [time-nuts] Description - GR 1120-AB Frequency Standard

Jim, Thanks for following up on this. The thermoswitch that I'm looking for closes on reaching a trip temperature of 78C. The original unit was made by Princo. I wonder if your friend could tell me if he has any leads on a 78C thermoswitch. Thanks again, Russ -Original Message---

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard

design was completely revamped. No double oven. Lower power requirements. The 1120 was described in the April 1961 issue of GR Experimenter. Best Regards, Russ WA3FRP -Original Message- From: Peter Putnam <[EMAIL PROTECTED]> To: Discussion of precise time and frequency measurement

[time-nuts] Description - GR 1120-AB Frequency Standard

Max is correct. The GR 1120-AB contains the following units in a standard relay rack: The GR Standard Frequency Oscillator 1113-A with an output frequency of 5 MHz. This unit is settable to 1 x10 -10 with an output of 1 V RMS. Located in the relay rack above the Standard Frequency Oscillator is

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard

Hi Mike, Yes I feel that you have nailed the root cause of the failure. That explains the failures observed here. Thanks and Best Regards, Russ -Original Message- From: Mike Monett <[EMAIL PROTECTED]> To: time-nuts@febo.com Sent: Wed, 20 Aug 2008 5:14 am Subject: Re: [time-nuts] Rest

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard

Phil, I didn't believe that the thermoswitch was the problem, at first, chiefly because of the simplicity of operation. Eventually, after checking wiring, a carbon resistor that is in series with the thermoswitch, and components around the inner oven control circuitry, I removed the thermoswi

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard

Hi Neville, Voltage across the thermoswitch contacts in less than 10VAC. Current is 6-8 mA. Once in failure mode, the mercury column passes the 78C point without causing circuit closure. Instead, a rapidly pulsating open / close with an internal resistance of 50K - 300K is observed. Circui

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard

Phil, The details of the thermoswitch failure are not completely clear. Intermittently, the mercury column will pass the 78C point without causing circuit closure. Instead, a pulsating open / close with an internal resistance of 50K - 300K is observed. Circuit closure eventually happens at a t

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need assist...

quency Oscillator and part it out as > needed > > 3. find a suitable replacement for the original thermoswitch (78 C - > closes circuit when temperature is reached) > > > I was wondering if anyone on this list has any sources or leads for #1 > and #2 and any opinions on a source for

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard - Needassist...

Hi Bill, The Tempco units look great. My original Google search came up with similar Fenwal units that are a bit larger sizewise. The size of the Tempco units appears to be a fit into the space reserved for the original thermoswitch. Thanks for the assist! 73 Russ WA3FRP

Re: [time-nuts] Restoring GR 1120-AB Frequency Standard - Need

Sorry for missing enough detail on the original thermoswitch. The original thermoswitch was a unique design that I have not seen elsewhere. The Princo thermoswitch was a modified mercury thermometer with two electrodes installed. When the temperature rises, the column of mercury comes into co

[time-nuts] Restoring GR 1120-AB Frequency Standard - Need assist...

(78 C - closes circuit when temperature is reached) I was wondering if anyone on this list has any sources or leads for #1 and #2 and any opinions on a source for #3. Thanks Russ WA3FRP ___ time-nuts mailing list -- time-nuts@febo.com To unsubscrib

[time-nuts] Paper for HP 117A

Allan, I use Amprobe 850D chart paper in my HP 117A. I've found that this site has the lowest prices: _http://www.tequipment.net/AmprobePriceList.asp_ (http://www.tequipment.net/AmprobePriceList.asp) If you find a better source, please let me know. Regards, Russ _