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Big Bad Bob Big Bad Bob is offline
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Default Does anyone have any Eico tube stereos or manuals?

On 12/29/18 17:07, wrote:
I have a new power transformer, which says "for Eico Stereo". But that
is all I know. It's just a hand written label, stuck on the bottom.

The case has these numbers stamped on it. 30002-3 (there is a "H" below
that).

It has 5 wires on the secondary. Two are 6.3v filament. The others are
the high voltage with roughly 285 volts on each side of the center tap.
(570v total).

I'd like to find out what model Eico stereo it's from, so I can
hopefully find a schematic and see what tubes it was made to power.

It's a fairly large transformer. Not as big as the old ones onthe old
tube tv sets, but still large.


hmmm... I'm guessing it's for a console stereo with maybe 10W per
channel. Most of the heater supply would be for the FM radio, all of
those IF amplifier tubes and stereo detector. The final stage might be
6BQ5 or similar, maybe even single-ended. I've seen that, actually...

The output DC would be around 320V probably, coming out of the rectifier
tube [unloaded], good enough for 6BQ5-based amplifiers which aren't
supposed to exceed 300V (from what I read). With a proper load on it,
the running DC volts would be around 300V or so, and cathode bias on the
output tubes would make them operate within their limits. But yeah this
would be a typical config for a home stereo system from the late 50's or
early to mid 60's.

Interesting it's made by Eico. I had an Eico tube preamp ages ago that
was originally a kit. I used it with a tube power amp for decades
before the output transformer went out in one channel and I had no
source for replacements...

online searches show vintage tube equipment by them that might use the
transformer you have.


--
(aka 'Bombastic Bob' in case you wondered)

'Feeling with my fingers, and thinking with my brain' - me

'your story is so touching, but it sounds just like a lie'
"Straighten up and fly right"