Fox 400 Mobile Linear Schematics Needed.

[fm325]

Hi All,
I just received a Fox 400 linear and was hoping that someone out there has a copy of its schematics. It's a 4 pill (1446) amp that's built better than some I've seen. Anyway, thanks. Be well.

 

[AudioShockwav]

Can you post pictures of the Amp, inside and out.


73
Jeff

 

[fm325]

Hi Jeff,
here are the pics. Maybe it's similar to another amp you or the others might know of.

Regards,
Frank

 

[nomadradio]

Ghost of Billy. As in Billy D. Ward.

It's a "Gray 300" with a different name, and 2001 RF transistors.

Has Billy's bonehead "neutralizing" trick where the black wire feeding the radio's drive to the Lo/Med/Hi switch is twisted alongside the wire that carries output power to the antenna socket.

Has no operating bias, and will sound like doo-doo on sideband. As a bonus, it may oscillate and hold itself keyed up when you unkey the mike on sideband.

Might behave on AM, might not.

Surprising part is that it's not blown up.

If it appears to behave itself, you're good to go for AM. If it ain't broke don't fix it. I would not recommend trying to modify this one to sound good on sideband. The stability problems it's already likely to have would just get worse.

I can't remember ever laying eyes on a schematic for this one. The circuits are so generic I don't remember ever needing a diagram.

73

 

[fm325]

Thanks for the info Nomad Radio.
I know the previous owner used the amp to talk skip on AM. I guess that's why it hasn't yet blown up. I wondered about the twisted RF input/output wires myself. Why would someone do that? Looks like a recipe self oscillation, as you pointed out.
I guess that I'll use it for a while and then sell it, while I can!

Thanks again, 73's,
Frank