[Amps] Amplifier lifetime

[Carl]

----- Original Message ----- 
From: "Jim Thomson" <jim.thom at telus.net>
To: <amps at 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 at miamioh.edu>
> To: Manfred Mornhinweg <manfred at ludens.cl>, amps at 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 


---
This email has been checked for viruses by AVG.
http://www.avg.com