View Full Version : Tuning into an ongoing SSB QSO with separate TX/RX
08-31-2010, 04:21 AM
What is the best way to tune a transmitter into an ongoing SSB QSO/Net when using a separate Rx/TX so that you're more or less on frequency with them? I'm using an SX-101A and HT-32A.
08-31-2010, 05:47 AM
Get your receiver tuned correctly onto the QSO. Then turn on your Tx "spot" function or if you don't have that, key it up and while listening on your Rx, tune the Tx until it is zero beat.
Of course you want to minimize interference to the ongoing QSO. Just like with even a modern radio, I would do preliminary tuning ten or twenty Khz away. You can do any touch ups after you are on frequency (quickly and discretely).
08-31-2010, 11:02 AM
Yup, take and Zero Beat the nearest frequency away. And since your receiver should be disabled when you are transmitting, you might not ba able to use that to tune yourself in. A favorite trick I use is to take a lot newer digital read out radio and turn my transmitter power down as low as it will go or on SSB turn the mic gain all the way down, turn on the newer radio and turn the mic gain up till just where I can hear myself on the other radio and tune myself in. That's another reason I like having several radios around.
08-31-2010, 11:26 AM
i'll tune the receiver onto the freq I want.....then get the TX within 10 or so K ...tune the finals into my dummy load...flip to your antenna and tune the antenna and retouch the finals
then flip the RX to "receive" instead of "stand-by" (I have a sx-100 and in the receive position it doesnt matter what the TX is doing) flip the TX back to the dummy load,turn down the volume and the sensitivity on my RX and tune the TX for frequency .............
after you flip off of your dummy load back to the antenna and turn your sensitivity etc back up DOUBLE check that you flipped the receiver back to "stand-by" so that it goes into stand-by when you key the TX instead of unleashing a Hendrix worthy wall of feedback onto the airwaves:D
08-31-2010, 01:01 PM
I have an HT-32 Mark 1/SX-101A. I don't know about the "A" model, but on mine, the mic is live when the TX is in "Cal". You can then talk yourself in without disturbing others. Use headphones to avoid feedback. The manual mentions this method.
I also have an HT-44/SX-117. With these, the transmitter "Cal" function is used to zero beat and it is then on frequency. It works.
The manual for the HT-32 also mentions this method by setting the TX to DSB and zero beating with the RX. Despite many attempts at adjusting the TX both by the book and by ear, I've never been able to get the HT-32 to be on frequency on both USB & LSB using this method. I found one of the sideband crystals (I forget which) to be off frequency but replacing it didn't help so I just "Talk myself in".
08-31-2010, 04:08 PM
All of the "boat anchor" (and most of the "modern" equipment as well) have some residual carrier that can be received on a local receiver. Just tune this carrier for "zero beat" on the receiver. Turn down the microphone gain and then tune the VFO until nothing is heard on the receiver. Most transmitters have a "spot" function which turns on the lower stages but doesn't activate the antenna change over relay.
Watch the "S" meter on the receiver. After the frequency cannot be heard you will notice that the "S" meter will start to "flutter" very rapidly. As you approach the true "zero beat" this flutter will slow down until it moves very slowly. When this motion gets down to where the "S" meter needle goes from side to side like 1 or 2 times a second you can be assured that the frequency is, for all practical purposes, truly "zero beat". The speed of the "flutter" is actually the difference between the frequency of the transmitter and the frequency of the receiver.
09-01-2010, 12:38 PM
And if you get it wrong and are slightly off frequency, they WILL let you know it. Sometimes rudely and with no help at all (like you're too high or too low) and sometimes because on SSB unless you know the voice you're listening to it can be difficult to know when you're "properly tuned in."
Just words in case this happens to you, it's happened to me a few times!