Generic (cheap) Power MOSFETs ?

The popular N/P fets in this size in ( TO247) package are IRFP530/IRFP9530 and IRFP540/IRFP9540 in the ( TO220) package are IRF520/IRF9520 and IRF530/IRF9530 and IRF540/IRF9540. Ray

Sorry, Correction below.

IRFP130/IRFP9130

mounting

Thanks for the IRFP sugestion, its always the p-ch ones that put the prices up. I think I'll get a stock of IRFP240 and IRFP9240, 200V, 12 amp ,TO247 ones which seem to be the best bang per buck in the UK.

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

IRFP130/IRFP9130

mounting

In a similar vein. If an amp needs a rare or expensive or unattainable output hybrid block STK..., TA..., Si... I tend these days using a relatively cheap for its performance, 100W TDA7294 instead. Small enough to place upside down or 2 together for 2 channels, with extra clamping and with a strip of matrix board on the new block pins then insulated wires crossing over one another to the original pad positions. It is usually possible to work out the DC rails, i/ps,o/p, comp, mute lines even if a pinout for the original is not available.

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

I do miss those Maplin 150 watt mosfet modules, great for resurrecting old stuff like H-H PA amps and the like. There`s nothing quite like them now, I must have built over a hundred, and most of them I bet are still working.

Ron(UK)

to

with

crossing

lines

Assuming you put in spring clamps, or such, then cutting off the protruding tab of the TDA7294 leaves a block only 20x10x4 mm , so 2 easily go in the space of an STK... etc and those are usually quite a bit less than 2x 100W. I wonder if they're bridgable, I'll have to dig out the pdf.

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

Ron

I always used to favour the ILP modules for the same purpose. Remember them ? They always used to advertise in Practically Witless magazine. For many years, they disappeared, then I tried searching them on the 'net a few years back, and I found a piece by the guy that was originally involved with them, and it seemed that he was going back into production. I just put it into Google again, and it came straight back with the top hit, so it seems that they are in production again now. As I recall, these were very 'plug n play' also with only + / - power, gnd, in and out connections, and were just about bomb proof. Might be worth getting one in just to play with ... ??

Arfa

enough

old

now,

them

years

them,

play'

about

I seem top remember those were dV/dt suceptable to failure (fridge-switch syndrome) if you did not limit the i/p dv/dt

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

enough

and

protruding

The pdf shows 2 bridged example but 8 ohm minimum but I've seen 4 of these bridged in a high power mixer-amp so presumably 4 ohm in that case. I meant SVi not Si, the Technics things

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

Yeah, quite a lot of guitar and bass amps use a pair in bridge mode, Carslbro BassBomber springs to mind, tho I dont have a ct diag for one offhand.

They do need sufficient cooling btw

Ron(UK)

Oh cheers, I`ll take a look at those, I built a 200w power amp using them way way back.

Ron(UK)