"Michael Black" wrote in message
...
"Nelson" ) writes:
Gents,
I have a Heathkit GR78 here, which is quite lively on most bands.
But
the top band 18-30 mHz is near deaf and almost impossible to align.
Anyone
very familiar with this rcvr?
Cheers,
Nelson
Is that the portable, the one that came out in the late sixties or
very early seventies?
If so, keep in mind that it becomes a double conversion receiver on
that top band, and maybe it's not an alignment problem but that the
conversion oscillator is not working (the mixer stage for the extra
conversion is a stage of straight amplification on the rest of the bands).
Michael VE2BVW
Michael, Robert,
That's the one. I have the manual and schematics from BAMA. The second
oscillator appears to be working, according to a digital radio I use as a
"sniffer". I'm still going thru it, but had to stop to replace the dial
cord. Two steps forward, one and a half back... some of the R's and C's are
off the mark, too, and have to be replaced.
I suspect the slugs have all moved... it was being pitched when a friend
caught it a foot above the garbage can or maybe in the can. I'm hoping to
find out how to start alignment from scratch. It appears the coil slugs
were all factory-set when it was sent out as a kit, and those settings are
off.
Cheers,
Nelson
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