Rewiring H&H S500D

[lousy_bassist]

Does anyone have a manual for one of these babies? Or even access to a unit wired for this country? Here's my dilemma, I'm a relatively recent arrival to this country, and I brought my trusty old power amp with me, but somehow in the move I have managed to misplace the manual, so I am unsure how to wire it for 120V (it's set for 240V it's old home voltage). Some chap on another forum was kind enough to send me a copy of his manual, but unfortunately it was missing the pages that covered the rewiring (everything from Chapter 3.3 was present, I guess the wiring info is in the earlier chapters?)

So does anyone know what coloured wire goes to what terminal and what pins to bridge? I'd rather do it from the manual than suck it and see (or buzz it out and guess), as there are numerous (nine?) terminals on the primary of the toroid to cover a wide variety of voltages so it's more than the usual one way for 120 one way for 240 type affair.

Cheers in advance.

 

[SSLtech]

What is "this Country"?

The S500D was popular in Blighty, so perhaps you're moved to the US?

If so, I looked inside dozens of them (all failed DC) but never looked at the 120/240 options.

How many wires or terminals on the primary of the power transformer?

Keith

 

[lousy_bassist]

[quote author="SSLtech"]What is "this Country"?

The S500D was popular in Blighty, so perhaps you're moved to the US?

If so, I looked inside dozens of them (all failed DC) but never looked at the 120/240 options.

How many wires or terminals on the primary of the power transformer?

Keith[/quote]

Yes Blighty would be where I'm from, there's me forgetting the Internet is international again. It's wired 240V for UK and I want to wire it 120 for US.

Failed DC? Were you blowing them up for a purpose?

There's 6 terminals on the primary, and theres seven cables hooked up to the various terminals, not including the link across some of the terminals. I suppose if no-one has a manual, or one that is wired for 120, then I will go about buzzing out live and neutral, and trying to figure out the primary windings, probably two windings which are in series for 240 and need to be in parallel for 120 (but the right way round otherwise one will cancel the other) and the extra taps are for voltages like 220 and 100 which would probably be taps on the two windings to cope with subtler voltage differences.

I recall from when I had a manual it had a multitude of voltage options, hence me hoping to go the simpler route :wink: the chap that sent me a manual did say he could try and get a picture of the internals from whomever he had sold the amp to. He had suggested someone here might have one to hand.

 

[SSLtech]

[quote author="lousy_bassist"]Failed DC? Were you blowing them up for a purpose?[/quote]
No, I was blowing them up for a porpoise. (he was big into aquatic insurance fraud) :wink:

No, those H||H S500D's became known as "Hissing Heap S-500 DC's! -Keep the cooling 'tunnels' clear of dust, or the transistors that depend on the cooling get stressed. One goes Collector-Emitter short, and you lose whatever is connected to it that isn't lucky enough to have a capacitor in series with it (e.g. HF horns)

You can try this: If you can beg borrow or steal a 120-240 step-up transformer and you know your way safely around an AC voltmeter, you can power it up on 240 and measure between multiple combinations of primary terminals. Some will have probably have 120 volts between them. Do some detective work and you can figure out that they're probably wired in series at the moment. there may be taps for 100, 110, 120 and a second set of 100, 110 120. That could be done with 7 or 8 terminals for example.

If nobody else chips in with more specific knowlege, it's probably do-able, though it depends on how safe you feel working on quite hi-voltage AC. I could do it, so could (probably) a TV-repair guy in the local strip mall, if you're not confident of your abilities.

Or you could ask if there's someone else in your particular part of the USA.

Keith

 

[lousy_bassist]

[quote author="SSLtech"][quote author="lousy_bassist"]Failed DC? Were you blowing them up for a purpose?[/quote]
No, I was blowing them up for a porpoise. (he was big into aquatic insurance fraud) :wink:

No, those H||H S500D's became known as "Hissing Heap S-500 DC's! -Keep the cooling 'tunnels' clear of dust, or the transistors that depend on the cooling get stressed. One goes Collector-Emitter short, and you lose whatever is connected to it that isn't lucky enough to have a capacitor in series with it (e.g. HF horns)

You can try this: If you can beg borrow or steal a 120-240 step-up transformer and you know your way safely around an AC voltmeter, you can power it up on 240 and measure between multiple combinations of primary terminals. Some will have probably have 120 volts between them. Do some detective work and you can figure out that they're probably wired in series at the moment. there may be taps for 100, 110, 120 and a second set of 100, 110 120. That could be done with 7 or 8 terminals for example.

If nobody else chips in with more specific knowlege, it's probably do-able, though it depends on how safe you feel working on quite hi-voltage AC. I could do it, so could (probably) a TV-repair guy in the local strip mall, if you're not confident of your abilities.

Or you could ask if there's someone else in your particular part of the USA.

Keith[/quote]
OK, Now I feel like a dummy, I hadn't even thought of measuring it with voltage applied. Dusts off diploma Electrical Engineering, guess I know my way around an AC voltmeter after all :wink:

Surely 120V isn't really high voltage, it's just a tickle. Come to think of it in 120V mode the secondaries might be higher than the primaries. I'm actually running it off a step up transformer, sort of, it's a variac wired backwards but it does the job.

I fear to ask where you were running your DC's, I've never really seen much dust in mine, in normal use, is there some big difference between the DC's and the D's? Mine just pulls in air through the front panel and blows it out the back, and I really need to be pumping the bass for a while before those fans even kick in.

Well if no-one jumps in at this point I guess it's time to fire up the 87 and get going. Good luck with flipper and his amps.

 

[SSLtech]

[quote author="lousy_bassist"]is there some big difference between the DC's and the D's?[/quote]
The S500DCs are S500Ds that have gone DC! :evil:

They were in PA system racks... used in all sorts of dive gigs, amplifiying terrible bands. They developed a knack of recognising really bad music and stopping the gig by going DC.

(great Bass end when they worked though...)

Keith

 

[lousy_bassist]

[quote author="SSLtech"][quote author="lousy_bassist"]is there some big difference between the DC's and the D's?[/quote]
The S500DCs are S500Ds that have gone DC! :evil:

They were in PA system racks... used in all sorts of dive gigs, amplifiying terrible bands. They developed a knack of recognising really bad music and stopping the gig by going DC.

(great Bass end when they worked though...)

Keith[/quote]
Huh? My S-500D is wired DC, there's a little link on the driver module to do it. Yes nice bottom end, but a nasty thump when you turn 'em on, even if you have the DC balance set right. I should probably wire it AC again. I imagine the DC balance wanders a little until they are warmed up.

 

[SSLtech]

no... I mean one that has failed and puts out full DC rail voltage into whatever is unfortunate enough to feel it's wrath! :twisted:

(hence "Hissing Heap"!) :grin:

Keith

 

[SSLtech]

By the way... these things have cool electrofluorescent front panels, too!!! :green:

Keith

 

[lousy_bassist]

Looks like a company called MAJ Electronics still deals in H&H stuff, they offer a PDF of the manual, so I can actually get them to send me a copy, and spares if I needed them. Looks like they also still build H&H alike amps if anyone cares.

http://www.majelectronic.co.uk/index.htm

Never actually managed to see one break I confess, I worked in a place long time ago that had a half dozen of these for 'lab use' they would use a signal generator, or voltage calibrator as the input and use them for pushing current into coils. Even hammering them like that in DC mode, they never broke. I guess fuzz must be their mortal enemy, I'll keep mine clean :wink:

 

[henk]

If you need new fets that look at exicon or magnatec site.

 

[BYacey]

These didn't use Fets. This is a Bipolar output, however the "V" series used Fet outputs.