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Phil Allison[_2_] Phil Allison[_2_] is offline
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Default Audio output transformer


"klem kedidelhopper"

I need to install a 60 Watt paging amplifier on a job. The maximum
load at this time is 42 Watts, however we need to have a slight amount
of room to move in the future. So I felt that 60W unit would be a good
cushion. I currently have in the shop a nice Technics 100 Watt mono
amp that I rebuilt and have no plans for. I would really like to sell
this to the customer to use for this application. The problem is
though it does not have the 70V output that I need. So I had two
thoughts. The first is can I buy a transformer that will have a
primary of 4, 8, or 16 ohms and a secondary which will provide the 70V
output that I need, and handle at least 60 Watts RMS? The second
thought is this: I have a number of 60Watt amplifiers in the scrap
pile with good transformers I'm sure. The schematics show these
transformers hung on the outputs as though they were a speaker load. I
have no idea what the primary impedance could be though on any of
these transformers, but I was wondering if it is anything close to
typical speaker impedance? If it was then perhaps I could pull one of
these from a junker, hang the primary across the Technics amplifier
output, (which I think is 8.0 ohms} and then have my 70V output? Has
anyone ever done anything like this? Of course I would do a load test
on the amp/transformer combination before selling it. Thanks for your
thoughts on this. Lenny



** The Technics amp will probably blow up.

You cannot use 70V line *step up* trannies with domestic hi-fi amps.

Line voltage power amplifiers are specially designed to drive the included
step up transformer - which presents a lethal load to most SS amplifiers.

BTW

"Technics mono 100W amp" leads to no particular model on Google.

So what the **** have you really got ??



..... Phil