[R-390] Pictures of my Motorola R390A

[n4buq at knology.net]

On Mon, 15 Jan 2007 11:42:04 -0600, "Don Reaves" <don at reatek.com> wrote :

> Nice pictures, Barry.  I like the way you right angled the balanced 
antenna
> input to a Twinax balun.  That lets you use less depth for a cabinet.  
Have
> you noticed any signal loss through the balun vs a direct connection?
> 
> 
> Don

I haven't done any real measurements.  I seem to recall not hearing much if 
any difference with or without it.  I use it primarily for a convenient way 
to get to a BNC connection.  A little impedence matching along the way 
doesn't hurt either.

I don't know if I forwarded it to the list, but the little box on the 
inside of the back panel houses a line filter and 12VDC power supply for 
the little fan.  There's another plug for another fan if I ever decided to 
put one on top.

It's a bit hard to make it out, but the black square in the upper left hand 
corner is the main power switch.  It saves the R390A's microswitch.

The three BNCs on the back were intended for both antenna inputs as well as 
the IF output.  I never got around to hooking up the unbalanced input 
connector.

The two RCA jacks are for Local (through the matching transformer) and Line 
output and the wingnut is for ground.  I wanted the back panel to be 
a "cleaner" version of the back panel on the radio with just the necessary 
connection points with quick-disconnects for them.

I took the pictures for someone who might be interested in a swap for a KWM-
2.  Not sure if I'll do it, though.  I put a lot of work into it and it 
works great so I might just miss it too much.

Barry - N4BUQ