----- Original Message -----
From: "Jim Thomson" <jim.thom@telus.net>
To: <amps@contesting.com>
Sent: Thursday, October 05, 2017 3:13 PM
Subject: [Amps] Amplifier lifetime
Date: Thu, 5 Oct 2017 08:59:49 -0600
From: Jim Garland <4cx250b@miamioh.edu>
To: Manfred Mornhinweg <manfred@ludens.cl>, amps@contesting.com
Subject: Re: [Amps] Amplifier lifetime
<Hi Manfred,
<I've got an NCL-2000 that has a similar history to yours. Like you, I
seldom use it, but think it is a well-designed amplifier and arguably
the nicest styling of any amp before or since. Replacement tubes are a
problem, of course, but I've got a couple of spares on hand. As I
recall, the bias circuit is quite clever and, with updated components,
works very well.
Interestingly, my NCL-2000 blower is rather quiet and has never posed an
irritation. I'd be interested in hearing comments on that issue from
other owners.
One design issue I've never liked with the amp is the T/R relay, which
uses a 6VAC coil. This rules it out for use with modern transceivers,
unless one uses an isolation circuit. In my station, I use my StationPro
controllers for my amplifiers, which can accommodate any AC or DC
antenna, so that isn't a problem
73,
Jim W8ZR
### 6 vac X 2.828 = 17 vdc. Use a 12 vdc vac relay, problem solved.
Im sure the oem blower could be replaced with one of the myriad of blowers
out there from ebm papst, or Dayton. The newly re-designed dayton blower
line up
draws just half the current of the old versions. New version all use
ball bearings.
Old versions use sleeve bearings. Then there is Kooltronics and a bunch
of other blower
makers as well. They should be good for 40 K hrs.
Jim VE7RF
The AC/Plate and antenna relays both use 13.6V AC coils right off the
filament winding.
I replace mine and customer AC relays with 12VDC and get that off the same
filament winding. No more hum or arcing due to poor insulation.
For the antennay relay about 3.3VDC operates it just fine which comes off
the same source and is also regulated.
Blowers are often fine if taken apart, cleaned and relubed with synthetic
lube which doesnt attract dust & dirt. My two oldest amps, one on 6 and the
other for 160-10 are prototypes and still on the original blowers. I have 3
other NCL's plus a few parts whores.
Carl
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