SIGMOTEK ITC-3 Frequency Counter

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I have bought myself a frequency counter from a hamfest -SIGMOTEK ITC-3.

I have searched the internet for a manual-no luck,so far . Would anyone be able to advise the correct way of connecting the input to this scanner to my radio -IE, I think I need a bnc 3 way adaptor and short 50 ohm cable . Is this correct.

precautions,, transmitting ? will the counter handle the rf wattage ? or is this a no-no ?

Thanks You

bruce
 

n0nhp

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DO NOT put the freq counter on your transmit line, you will let the magic blue smoke out and pay the magician or his apprentice to replace it.
The second image here > inside circuits > frequency counter preamp l9724 - Next.gr will give you one of many possible attenuating taps to sample the transmitted signal.
The top diagram is if you want to use the counter to pick up signals off the air using a short antenna.
Bruce
 

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WA0CBW

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Another easy device to construct is an "ISO-T". This is a UHF T that you remove the center pl259 center pin. The frequency counter connects to the center pl259 with the pin removed and the transmitter connects to one of the SO239's and the other SO239 connects to a dummy load. This provides about 30-45 db of isolation between the counter and the transmitter. Technicians use these all the time to sample RF from a transmitter or inject RF into a receiver to measure desense or site noise for repeaters or receivers.
BB
 

majoco

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connecting the input to this scanner to my radio
I'm not quite sure what you want to do. The signals that come from your antenna to the scanner are far too weak to make the frequency counter work, yet you mention "RF wattage". I take it that this means you are going to transmit some power up to the antenna, in which case you'll only need a "Sniffer" to get the signal into the counter - no direct connection at all - the Tee piece with the pin cut off works well but you have to make absolutely sure that you have it connected right - there's no second chance.

Anyway, why do you need to know your transmit frequency? If you don't have a licence, you are not allowed to use a transmitter that is not crystal controlled to prevent you transmitting on unlicensed frequencies.
 
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Hi Nonhg ,

I'll build one of these ,that lower,simple one .

What would they be called ,and are any for sale . I suppose they come with the counters ..

Thanks

Bruce
 
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