Collins 18 S-4
Mark, I built a control head. No big thing. Also, AM is the deafult.
All you really need do is plug in a mic on the front panel. RF and AF
gain must be controlled externally, of course. The crystals you have
won't do you much good but you can have a set cut for.. say 3885, or
such. That's what I did. I hooked a Heath VFO up to the transmitter
and it worked OK. The 18-S4A receiver is much better than the straight
unit inasmuch as it has a mech filter installed. The straight unit is
as broad as a TCS! Also, I did not use the fixed elements in the TX
tank circuit. I brought out the "untuned" RF into an external
PI-network (instead of the tuner) for 80 meters. That way, I could tune
wherever needed and not worry about the fixed freq. tank components. I
have both original Collins 18-S4 and 18-S4A manuals. Unfortunately, I
no longer have "unlimited copy capability"...hi!
MilRad wrote:
Great topic here as I recently decided to try and get my 18S-4 on the
air. I am looking for the 314S-4 control head if anyone out there has
one. I'm not sure how to change from CW/AM without it. I have the rack
and tuner.
I'd like to get the schematic and manual also but don't want the large
investment in case this doesn't get off the ground. I have the small
handbook but that was a bit of a dissapointment as it doesn't have tech
data in there. I believe my unit is complete as it has most of the
crystals. Not Ham band but close. I'll have to check what tuning units
are in there.
73,
Mark
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