[Collins] 160 meters

[Dr. Gerald N. Johnson, electrical engineer]

Worked in my Dad's 75S2 with the extra crystal board without loosing 80
meter coverage. Meant moving one 80 meter crystal to the extra crystal
board. And I made it work at least 20 years ago, didn't need a write up.
My dad didn't think it was worth the bother so took the mod out years
ago.

73, Jerry, K0CQ, Technical Advisor to the CRA

Merle wrote:
> 
> For what it is worth category, back in 1997 there was a great article
> going around about adding 160 meters to you 75S-3 / series S-line
> receivers.
> 
> It summed up as follows.. you would add it to the low portion of
> the 80 meter band on your 75S receivers, position 1A of the band
> switch  It required purchasing a xtal  4.955 MHz. This would allow you
> to tune 1.8 to 2.0 MHz. You also have to add capacitance to the RF
> amp. about 240 pf  ( C4 ), the Crystal Osc. about 200 pf ( C70 ) , and
> the Output of RF Amp. about 510 pf ( C17 ).
> 
> This will cause you to lose 80  meter function in position 1A and 2A
> as there are resonant 1.8 - 2.0 however position 3A 3.8 to 4.0
> MHz. work as they should.
> 
> If you want to transmit on 160, well, you are on your own Hi.
> 
> 73
> Merle
> 
-- 
Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.