Carlsbro S600M, 1981 600W slave amp

[N_Cook]

If anyone should have any info on the triac ? mains power protection, or
maybe similar Carlsbro amp , th/sw on heatsink plus other stuff monitored
presumably. Its in an awkward area to get to, a lot crammed in a small box.
Anyone happen to no basic data on Carlsro badged TO3 audio o/p devices
ERD1159
?
(if on the off-chance of any schema, please confirm here , severe filters on
all my www divulged em accounts)

 

[David Nebenzahl]

I was going to suggest contacting Carlsbro direct, as I had in the past
found them helpful. However, lokking at their website, sadly it would appear
that they are in administration, as of earlier this year ... :-(

Is "in administration" Brit-speak for what we call in bankruptcy?

 

[David Nebenzahl]

For all intents and purposes, yes, but AIUI theoretically sort of a stage
before declaring your company truly bankrupt. If you are in serious hock to
the bank for instance, and they are worried that they are not going to get
paid because of poor trading performance, they may force you into
administration, from which place, the administrators may ultimately declare
you bankrupt, if they determine the company is beyond saving.

Ah, so. I think we call that being "in receivership" over on this side
of the pond. (If I'm wrong I'm sure someone will correct me.)

Points to your term for being more direct. (Like the beauty of the term
"lift" compared to our lugubrious "elevator".)

 

[David Nebenzahl]

Yes.

Well, not quite, if you read Arfa's reply.

 

[Bob Larter]

Is "in administration" Brit-speak for what we call in bankruptcy?

Yes.

 

[N_Cook]

I was going to suggest contacting Carlsbro direct, as I had in the past
found them helpful. However, lokking at their website, sadly it would appear
that they are in administration, as of earlier this year ... :-(

Another long-standing British company bites the dust.

Arfa

Once the "administrators" (vultures) go in there is little chance of
survival. With all the accrued debts and then the costs of the
administrators on top. I was an unsecured creditor to the failure of one of
the last UK component makers, Cambridge Capacitors, Romsey , Hants . As part
of that process you get breakdowns of all costs. 600 GBP per hour for the
head administrator and 400 GBP per hour for his assistant etc etc on top of
all else.

If there is anything left to go to auction, I hope someone buys all the
manuals. I managed to buy the accumulated manuals of a large Southampton
electronic sales and repair business that was in Southampton from the 1950s
to failure about 10 years ago.

 

[N_Cook]

Oh they seem to come and go regularly. Some of the stuff they make isn't
at all bad, the rest is rebadged Chinese junk.

btw, If I recall correctly, and it`s the amp I thnk it is, it`s worth
checking the screws holding the output transistors to the sinks. Some of
the production run had anodised screws which made poor contact. I think
they were black and needed to be replaced with unplated ones.

Ron

All h/s screws needed tightening but all unplated. Distinctive feature all
sockets on the back XLR ,4 i/p and 4 speaker o/p one set of 4 female and
other male. I cannot, cold, see how this setup works
I'll have to desolder one each of the pairs of the th/sw (4 in total) , one
pair for each ch , seems one parallel pair for normal fan use (in series to
mains fan) and one higher temp parallel pair for overall cutout via mains
triac. As all seem to be s/c cold, perhaps one of an o/c-cold pair is
shorted. Then there is a triac crowbar on each output that presumably
activates the mains triac, 3 triacs in all, to confuse matters

 

[N_Cook]

Not a sw problem , a 47nF ,400V 1960s type yelowish cement cased poly cap
over a th/sw contacts was s/c. Had me bamboozled for a time.
So 2 n/o 58C th/sw in parallel for fan operation and 2 100C n/c th/sw in
series for cut out. Can power up now having sorted that conundrum out.

 

[N_Cook]

Power side works including the over temp th/sw system, now to somehow
reconnect the signal lines. Unfortunately another problem became apparent.
To avoid a 1 turn secondary on the torroid they passed the coach bolt
through a second anchoring plate with some insulation. Looks like 2 cut down
black plastic 1/4 inch socket outer rings. One either side of the hole in
the plate, but of course not high temp plastic and have softened enough to
deform , not actually making metal/metal contact but obviously not safe.

 

[Bob Larter]

Well, not quite, if you read Arfa's reply.

It's still pretty close. Think of the difference between Chapter 11 &
Chapter 14, for example.