Re: DP512 12 GHz Digital Prescaler


Hi Egge Siert,
You have only part of the story.

There is a TM 500 Rubidium Standard. It is the PTB-100. It was made by the Efratom Division of Ball Aerospace which can be seen at
I have had two of these over the years.

There are at least two other TM500 GPS Frequency Standards. I made the first one in 2008 using a Rockwell-Jupiter GPS Receiver and a Phase Locked Loop designed by James Miller G3RUH. I found the design on the internet. They are no longer there but I saved a copy. I will include it in a PDF documenting both of the GPS frequency standards I built.

I built his design in a single wide TM500 prototype. I named it my "FS501 GPS Frequency Standard".
In 2012 John Miles KE5FX gave a much better GPS Receiver module. This was a Trimble Thunderbolt. I combined this with a wonderful Monitor program designed by Didier Juges KO4BB, who, among other things maintains the manuals depository at
That became my "FS502 GPS Frequency Standard". That has been working ever since 2012.

I recently was given an HP Z3801A GPS Receiver which, according to John Miles is an excellent GPS receiver. Unfortunately the PC Boards inside it would require a triple wide TM500 to accommodate them. So I may not be able to make that the basis of another GPS plugin unless I can find a 3-wide TM5xx plugin to take apart for its case. I do have 6 Nixie Tubes for it because something this accurate only deserves the best possible display. I am pretty sure I can fit the Nixie Tubes into the HP Z3801A but it will be tight.

I really like how you did the front panel of the GS510. What did you use? I would love to be able to duplicate that same material and style that Tek switched to even if it is not as durable as the anodized aluminum front panels of most of the 7000 plugins and TM500 plugins.

Dennis Tillman W7pF.

-----Original Message-----
From: [] On Behalf Of Egge Siert
Sent: Saturday, July 11, 2020 1:37 AM
Subject: Re: [TekScopes] DP512 12 GHz Digital Prescaler

Hi Joe,

From a German eBay Member (I assume a former Tektronix Germany employee) I got the following answer:

"Guten Tag, ja ich weiƟ es, es sollte mal einen Eigenbau eines Prescalers bis 14 GHZ werden, das Projekt wurde aber nie gestartet.

Mfg Klaus Chudzinski"

The earlier mentioned Rubidium Standard Plug-In was in fact a 10MHz GPS Standard named GS510. Pictures of it are now in the posession of TekWiki.


Egge Siert

Dennis Tillman W7pF
TekScopes Moderator

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