[Milsurplus] A thought experiment.

[Hubert Miller]

I have always liked the looks of the BC-654 and BC-1306, but as you know, their frequency range is only slightly useful.
BC-654, 3850-5850.    BC-1306,  3800-6500.
As we know, it is easier to pad tuned circuits down and lower the low end.
But i always liked 40 meters more. More long-range possibility. So i wondered, could these radios be moved to 40 meters
at the high end of their range. The receivers wouldn't be all that hard to do. The 1306 receiver HFO already tunes to
6500 + 455 kHz. Using the 'high image' of that 6955 KHz will tune to 6955 + 455 kHz = 7410 kHz. Then you have to
retune the RF and insert a padder in their tuned circuits to limit the top: bottom ratio.
Transmitter tracking is more of a challenge. Though maybe not that bad; it only has to track reasonably well across
7000-7300 kHz. I looked at the BC-654 output circuit and it has 8 uH in the 307A plate; 5 uH will take it up to 7300+
kHz. Do-able, i think. The overall frequency change is less than 20% for the BC-654 and less for the BC-1306. My
conclusion is, it's do-able. I do have an ugly BC-654 that maybe could be a test bed.

I would NOT contemplate doing anything like this to a BC-1209, TRC-2, TCH, etc.
But BC-1306 and BC-654 are still out there in numbers.
So - is this:  Immoral ? Amoral ? Pointless ? Go for it ?
For now, and most likely forever, for me this will remain only a thought experiment. Job #1 is getting squared away,
not taking on another project, that's for sure. But i would like to know what you think about it.

I do have a BC-654 that has the receiver scale relabeled for down to 3000 kHz. I have not yet tried it out or looked
into it to see how successful this effort was.
-Hue
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20170224/eb384a10/attachment.html>