Okay, we’re on the home stretch. You should have a working receiver and most of the transmitter working, as well. All that’s left is to put the transmitter’s PA circuitry in place and get everything adjusted and aligned. First, we’re going to install everything except the final PA amplifier transistor Q16 (the IRF510B):

R1, R2 R3, R4, R6, R13, R18, R51

C3, C4, C8, C9, C13, C14, C15

D2, D3

Q2

That should be all of the parts except for Q16, the power transistor. If you see any other parts missing, now would be a good time to install them. Note that there’s a spot on the board for C30 but it’s not used.

At this point, follow the instructions on page 13 of the Survivor manual, starting at the “Transmitter testing” section. There are a couple of tests to be done prior to installing the power transistor Q16. If those pass, proceed to the next section in the instructions and install Q16 according to the directions. Then proceed to page 17 to continue with the transmitter adjustments and setting the modulation level. Once you’ve completed those steps, you ought to have a working rig.

But, just to be sure, I recommend setting up a second receiver so that you can listen to yourself as you transmit voice with the Survivor into a dummy load. Connect a dummy load to the Survivor’s antenna output. Then disconnect the antenna (if any) from your second receiver, and in its place connect a few feet of wire (clip leads work reasonably well) to the center lead of the antenna connector and then lay the wire near the Survivor’s dummy load. Fire up both radios and tune them to the same frequency (use the Survivor’s Tune mode to help you find its signal in the second receiver, if necessary). Once you’re on frequency, take the Survivor out of tune mode and instead transmit voice. You should be able to hear your own transmission in your second receiver if you use headphones (some fine-tuning of the frequency may be necessary).

Sometimes it can be hard to listen to yourself “live” like this, so an alternative is to record the output from your second receiver and see how it sounds on playback. You can do this either by connecting a patch cord from your receiver’s headphone jack to your computer’s sound card mic jack. Or, you might already have a connection in place in the form of a PSK sound card interface. Either way will work and will give you a clearer picture of how your transmitted audio sounds.

If your TX audio sounds good, you’re good to go. I noticed a little bit of a carrier along with my voice when I did this test, and I got rid of it by backing off the PA bias setting just a little bit. There’s another way to get carrier in your TX audio, too, and that’s if your BFO frequency is too close to exactly 9 MHz. In that case, the main carrier from the BFO is getting through the crystal filter instead of getting filtered out. Remember that, on transmit, the job of the crystal filter is to only let one sideband through, and to remove the carrier and the opposite sideband. And that’s the reason why the BFO frequency needs to be a little off from 9 MHz. You can hear this for yourself if you fiddle with the setting of CT1 while transmitting and monitoring your TX audio. Be sure to set it back where it needs to be.

At this point, you ought to have a working, ready-to-go transceiver. All that remains is to button it up in its enclosure. Don’t forget to follow the instructions on page 13 for setting up the digital dial to read out the operating frequency correctly. Finally, give the rig one more listen after you get everything buttoned up inside the enclosure. The metal enclosure will influence some of the components (mainly inductors and tranformers), so one last check is a good idea.

Congratulations! Now go put your new rig on the air!

 

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