Re: Amp - loss of power?

On 1 Oct 2005 22:40:27 -0700, "Ben Gray" <o2xtal@xxxxxxxxxxxxxxx>
wrote:

>> Do you have a sustitute rectifier?
>
> I have diodes marked IN4004
> The schematic specifies IN4007

IIRC, this is just a difference in voltage rating.
And, in practice, maybe just a difference in pricing
or specing from the same production run. Whatever;
2.5 amp 1000 PIV rectifiers are next to free
nowdays, so no biggie.

>> Do you have a substitute load?
>
> What do I need?

If I'm reading the schematic correctly, 435 volts
at, let's say, 100 mA is a load of 4350 Ohms and
43.5 Watts. A 4000 or 5000 Ohm resistor from
Fair Radio Sales or some other surplus supplier,
mounted in a safe (dangerous voltages; high temps!)
cage, should do fine. Don't allow children or
pets into the room, natch.

>> Also, can you measure line voltage?
>
> I have a multimeter and a strong will to live.

Then you'll have already eliminated the Edison as a
potential problem. But I haven't read (have I missed it?)
that you've measured the B+ (the high voltage supply
at the center tap of the output transformer).

The obvious inference from your symptoms is that the
standby switch is failing, so a few DC measurements
should go a long way. And all this (above) is
most likely unnecessary.

Please keep us informed, and keep one hand in your
pocket!

Good fortune,


Chris Hornbeck

"Let us change the world" -Marx

"Let us change life" -Rimbaud

"All power to the imagination" -France, 1968
.