Fwd: [BC] Worst Transmitter

[Richard Johnson]

Agreed on all counts!!! FYI, the RA-1000 at WARE only went
off-the-air when the standby generator wouldn't start and
the electricity was off from a thunderstorm or Northeaster.
One time a modulator 833-A cracked because there was a leak
in the roof of the transmitter shack. The transmitter was
still running, but it sounded a bit distorted so went to
the site to have a look.

ITA FM transmitters were not expected to run for more than
a week without rebuild. You would buy a roll of finger-stock
from Eimac and rebuild your spare set of tuning-lines while
sitting transmitter watch at the AM site, then pull an all-
nighter at the FM site installing the rebuilt lines.

Been there, done that.

 >> From: DHultsman5 at aol.com
 >> Date: Tue, 17 May 2005 08:11:18 EDT
 >> To: broadcast at radiolists.net
 >> Subject: [BC] Worst Transmitter
 >> Reply-To: Broadcast Radio Mailing List <broadcast at radiolists.net>
 >> Sender: broadcast-bounces at radiolists.net
 >>
 >>
 >> Subject: Re: [BC] The Worst Transmitter of All Time
 >> To: _broadcast at radiolists.net_ (mailto:broadcast at radiolists.net)
 >>
 >>
 >> I guess I would have to say I think the worst FM transmitter I 
ever  operated
 >> or worked on was the ITA  FM5000,  FM7500 and FM10,000.   Parasatic PA 
stages
 >> no variable neutralization you added or removed screen  bypasses.  No
 >> variable loading control on PA stage of the 5 K & 7.5K  models.  Inductive
 >> slider
 >> tuning with multiple right angle drives and  splines. Hi currents on the
 >> tuning
 >> sliders routinely overheated.  Mercury  vapor power supply filament
 >> transformers constantly going to ground losing power  supply,  Replacing
 >> with solid state
 >> rectifiers solved most of these  problems with PS, thanks for help from 
Bill
 >> Johnson with Wilkinson  Electronics.  I think the most reliable AM
 >> transmitter
 >> i ever had as a CE  was the Raytheon RA-1000.  I don't believe I ever had a
 >> failure on that  unit used only at night.
 >>
 >> Dave
 >>