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After replacing IC2, my rig is not keying itself. When hooked up to an antenna, I hear static, and a rhythmic ticking sound, which might be some QRN from something nearby.

but when I attempt to begin the aligned process, and put it into 8.7 PEAK BPF, it shows around 75% of the bars, and the number 2, upper right, which occasionally changes to 3. turning the adjustment on C1 does not appear to affect the display in any way - and there is no loud tone heard...no tone is heard at all.

I'm soliciting recommendations for the next step or steps. no O-scope here, though...just a multimeter.

thanks

K3ESE

...could it be that we're supposed to turn C1 many times in one direction, before any change is seen...? it sort of looked as though the entire range was limited to just less than fully engaged or disengaged.

K3ESE

Lloyd,
You're right about what it looks like, C1 is just like most tuning capacitors plates either fully meshed or open. One thing to make sure of is the band pass transformer, T1 (right?), is making good connection on all windings. The test signal is injected just about at the antenna connection so there's a few stages involved in getting good response.?

If you haven't already, start working through Hans' troubleshoot guide.?

Best of luck!

--Al

LL

At least one builder had a defective trimmer cap, so carefully examine it. Possibly you have something not connected somewhere. I would poke around with my finger with that test oscillator running. Wait I actually had to do that in my build, and I quickly found a solder joint I missed. The tone is huge when it arrives.

After you get a tone, that image calibration routine is way cool. As you are able to minimize the ticks on the display, it will rescale itself and the number will change. It will do this a bunch of times. When properly adjusted the audio image is way down.

I have too much on my plate now but I could help later. BTW our club is preparing for a group uBITX build. We are just arranging the group order. Yes Farhan is something like VU2ESE.

Cul OO Curt

Cap C1 can be something of a problem alright. First of all, the range from fully meshed to unmeshed takes only one half turn, 180 degrees. If you look at the cap carefully you can see what position the rotor is in with relation to the stator.
Second, soldering the stator pin(s) can be difficult to do without trouble. The stator is made of three plates each with a pin out to solder to the board. these pins are in effect a laminated ground pin. The problem I have seen on some QCX units I have repaired is that not all three layers of the pin get soldered properly. It takes more heat than the rotor pin, which has in some cases resulted in heat damage to the cap itself. I recommend turning the rotor until fully meshed before soldering as this provides the most protection from heat damage. Take a good look at the stator (grounded) pin connection to verify all three parts are soldered. If they are not, tuned circuit will not resonate and you will not be able to achieve a peak.
--
> I finally got it all together...now I can't remember where I put it<

Wes

AE6ZM

Sierra Vista, AZ

?

Use an Ohm meter to check the solder connections on the large torroid (T1). ?? If you did not get all the enamel off one of the leads you will see what you are seeing.? Measure at the pad and not the end of the wire.? If one winding is not soldered well, just hold the solder iron on the connection for about 10 sec and it will remove the enamel.?