[majoconz]

AHA! I had the very same problem with a Heathkit "Mohican" that I bought from our local net auction site - not as a kitset but built up. It was a deaf as a post but a bit of sleuthing showed that all the voltages were about right. The coil pack was supposed to be pre-aligned but it all looked a bit strange with trimmers all at one end and the slugs likewise.

Anyway, I managed to blast a signal through the IF and that tuned up nicely in the end - ceramic filters probably led the original owner astray. Similarly I got signals through the low and eventually the high frequency bands BUT the highest band 20 to 32MHz just would not align nicely. Bearing in mind it was low side oscillator injection and 455kHz IF - the instructions showed how to determine if it is set up correctly by looking for the image frequency but the front end was so broad that it was very easy to lose where you were. Often you could get signals at both ends but be deaf in the middle! Then I found that if you did get everything right the oscillator would stop at around 26MHz!

I made a dummy plate to cover the underside of the coil pack which helped with that problem and another flash of inspiration led me to using a digital tranny radio to find the oscillator! Genius! It worked - but it was not possible to getting it to track right across the scale - of course there were two points on the inductor where the frequency was right at the low end but then the high end capacitance was too much or too little and the centre of the band was a meg or two out! Another inspirational flash and I made it track at about a quarter of the scale from each end as a compromise - then the RF stages would tune up nicely. I was happy to put up with that but it annoyed me that it wasn't as good as it should be.

Go back to the instructions. It says " to set up the bandspread capacitor, set the bandspread pointer to the left hand end of the scale and adjust the capacitor so that it is fully meshed - tighten the grub screw" but then "Check that the capacitor is nearly fully open when the pointer is on the "SET" position on the dial" - this is on the high frequency end of the bandspread dial. BUT "nearly" is not good enough! There was still a lot of capacitance left which meant that the trimmer could not be set low enough! I cheated and set the bandspread capacitor to almost the end of its minimum capacitance and then set the scale pointer onto the set mark. Bingo! Now everything fell into place and I could get good tuning at the high frequency end with the trimmer at half it's range. A few runs through at each end and carried out a tracking error check and it was all pretty good. Of course I had to re-align all the other bands now that the bandspread cap had slightly lower capacitance than before but I was happy at last! I celebrated with something cold and mildly alcoholic!