Frequency measuring

ID: 185902
? Frequency measuring 
17.Mar.09 21:32

Eduard Hontele (B)
Articles: 16
Count of Thanks: 3

Dear radiofriends,

I still use my RF signal generator, a tube 100 Kc to 120 Mc model from the sixties. I want to monitor the frequency with a modern counter. In the highest frequency range the output becomes low and the counter isn't working stable anymore. The reading varies with the output level. I am looking for a circuit that is able to amplify and clip the sinewave  in such a way that it can be used as a stable output to measure the generator frequency. Has anyone built such a "counter driver circuit" ?




Eduard Hontele


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Counter Driver Circuits 
18.Mar.09 20:31

Bryce Ringwood (ZA)
Articles: 79
Count of Thanks: 2
Bryce Ringwood

Hi Eduard

I also still use my tube type signal generator.  The  frequency counter circuits I found so far seem fairly challenging (e.g. the crcuit in the 1994 RSGB Handbook), so I'm considering an "FC 130" frequency counter (sold under many brand names costing around Eur 100) or a new Chinese Signal generator(A "hobby type" instrument at about Eur 190 ). The FC130 counts from 1 MHz to 3GHz.).

Up to now, I tune the signal generator to the correct frequency using a radio with a digital display, zero beating to the display frequency.

Regards - Bryce

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fix your RF firts 
19.Mar.09 02:40

Maurice Hamm (NL)
Articles: 45
Count of Thanks: 2

I advise you to first examen the RF generator.

This by using a scope and try to bring the scales in that position that you can watch just a top of the signal.

Now you can watch if the signal is in ampl stabel or in freq stable as seen in vert or hor variation. Just the variation in beginning is an indication of the generator to inform you that is going to breakdown completely shortly.

Just begin with replasing some capacitors, mostly 80% casses afther this it is back in perfect condition. To start with the supply capacitors.

If using a seperate freq-counter it is not nessesary to tune the RF generator to adjust scaling precisely. Just use your counter to tune in on the disiared freq.

An Rf generator old & tubes are also designed as a precision instrument and can be measured with a brand new cpu counter, a signal is a signal, nothing special about.

just fix it befor it gets a non reparable defect.




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