[Swan] 700CX hum issues

[Mark Shaum]

David,

Make sure the power supply isn't wired for 240V operation.  You mention that 
tube filaments and the dial light barely are visible.  Check the power 
supply outputs with the rig not connected (and a jumper in place as 
appropriate to power up the PS).  Also make sure the cable between the PS 
and xcvr is correctly wired with no cold solder joints.

I have a 250C, 500CX and  a 700CX with SS-16B here.   I don't use the 700CX 
that often.  Maybe its the price I paid for a NOS pair of 8950's for it that 
makes me wary of using it a lot.  The SS-16B filter is a bit narrow for 
general rag chewing, but then again it was supposed to be a sharp and steep 
"dx" filter, significantly narrower than the stock filter.

I replaced ALL electrolytics on 3 out of 4 Swan power supplies here.  One of 
them definitiely had bad caps everywhere, the others had at least one or two 
that showed excessive leakage under rated applied voltage.

73! - Mark K9TR

Original message:

From: "David Shipley" <dhshipley at cinci.rr.com>
Subject: [Swan] 700CX HUM!!!

I recently bought a 700CX SS-16B off ebay! When I connected it and turned it
on it had a loud hum from the speaker. I took the cover off the rig and
turned it on again and I can see that the tube filaments do NOT light and
that the bulb for the dial light BARELY glows! I guess there's something
wrong in the power supply because the tubes and the bulb light if I connect
12VDC to the right pin on the connection! Am I correct??? Can you give me a
little help???
David Shipley....kf8ii