[Amps] LK 550-ZC

[Carl]

Amp International was the last name, Denny was selling into the commercial 
market.

The ZC included the day to day updates to the ZB, and finalized the ALO 
circuit, QSK, and the step-start and fan speed. Real late ones had a fan 
speed temperature sensor.

Carl
KM1H


----- Original Message ----- 
From: "Dick Green WC1M" <wc1m73 at gmail.com>
To: "'Paul Kraemer'" <elespe at lisco.com>; "AMPS" <amps at contesting.com>
Sent: Thursday, March 15, 2012 5:12 PM
Subject: Re: [Amps] LK 550-ZC


> As far as I know, there was no individual manual for the ZC. I think the
> "400/500 Series" manual was intended to cover all the variations in both
> series. I don't recall exactly what set the ZC apart from other models in
> the 550 series, but I think it was QSK. The BAMA manual has the schematic
> and some instructions for the QSK Board. Is there some part of the manual
> you specifically need?
>
> I happen to have a working LK-500ZC sitting unused in the basement. It has
> QSK, but I'm pretty sure it lacks the No-Tune option (it's been a long 
> time
> since I used that amp.) I don't recall if it has the "new" step-start
> circuit discussed in the BAMA manual, but I think so. It carries the Amp
> International label, which I believe indicates that it was one of the last
> amps made by Denny before the enterprise went under. The manual that I got
> from the previous owner is almost identical to the BAMA version, but 
> appears
> to be an earlier edition. Perhaps that means I have it backwards, and that
> the original company was Amp International and the last-gasp company was 
> Amp
> Supply, and that my amp is an earlier model instead of late one. My manual
> does have the pages missing from the BAMA manual (3, 15, 21-24), but those
> pages don't contain any critical information. The BAMA manual has more
> complete schematics and bills of material.
>
> I did a lot of repair work on the amp when I got it. The previous owner's
> wife had thrown something at him during a fight (a chair, I think), and 
> the
> amp got knocked off the desk. All three tube seals were compromised, and
> when the previous owner turned it on, the resulting arc fried the plate
> choke and a number of other components. I also replaced a 40m output cap
> that was actually broken by the blow to the amp. The meter bezels were
> damaged, too. I fixed all that stuff, added a glitch resistor to protect 
> the
> plate choke from future mishaps, replaced all of the meter calibration
> resistors (which had either deteriorated or were replaced by a previous
> owner with the wrong values in order to fool the ALO circuit, throwing off
> the meter readings), slightly increased the fan speed at the low setting 
> to
> prevent it cycling into high speed mode so often, and lowered the fan 
> speed
> in high speed mode so it wouldn't sound like a freight train.
>
> 73, Dick WC1M
>
>
>
>> -----Original Message-----
>> From: Paul Kraemer [mailto:elespe at lisco.com]
>> Sent: Thursday, March 15, 2012 2:29 PM
>> To: AMPS
>> Subject: [Amps] LK 550-ZC
>>
>> Can someone help me find a copy of manual for Amp Supply LK-550 ZC.
>>
>> I have the download from BAMA which covers the 550 but not the ZC
>>
>> Thanks
>>
>> Paul K0UYA
>
>
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1424 / Virus Database: 2113/4872 - Release Date: 03/15/12
>