Converting a 24V amp to 12V

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cb4ever104
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Converting a 24V amp to 12V

Post by cb4ever104 »

Hi All .

Just curious . Saw a 24V Zetagi B501P for sale . I was just wondering . Is it a lot of work to convert these down for 12V operation ?

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Re: Converting a 24V amp to 12V

Post by ch25 »

I suspect, that not much. 24V means 2x2 455's in series, need to be converted all paralel. Also bias circuit will need some work.
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Re: Converting a 24V amp to 12V

Post by cb4ever104 »

Hi Chris .

OK . I wasn't sure if the 24V was maybe dropped to 12V within the amp first , but that doesn't seem to be the case . I thought both amps might share the same main pcb . I'll email Zetagi for the schematics to get a better look .

Cheers

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Re: Converting a 24V amp to 12V

Post by Tim »

There are plenty of power reducer units available on eBay, that might be your easiest and simplest solution.
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Re: Converting a 24V amp to 12V

Post by cb4ever104 »

Actually I'll need to increase my PSU output from 12V to 24V . Not decrease it . Saying that I'm not that keen on these kinds of units . I'd prefer to modify the amp if it wasn't a big job.
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Re: Converting a 24V amp to 12V

Post by wa10 »

Modding a 24v amp to work properly on 12v is far from a small job,
24v Zetagi 2 transistor amps use the same pushpull configuration as the 12v amps but they use 28v transistors & run on 28v in a truck,

they usually have mrf422's or srfe1164's, also seen 2sc2510's & sd1407's in them but not from the factory,
different tuning, different components in the bias circuit, sometimes different value feedback components,

The later amps like zetagi b750 use b550 boards with a 78series regulator to run everything but the output transistors at 12v,
i think the older zetagis without the regulator used different resistors etc to work on 28v but its many years since i saw one.
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Re: Converting a 24V amp to 12V

Post by cb4ever104 »

wa10 wrote: 06 Jun 2018, 19:39 Modding a 24v amp to work properly on 12v is far from a small job,
Cheers for that wa10 ! Well . Don't think I'll buy it then . Looks like way too much work :)

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Re: Converting a 24V amp to 12V

Post by ch25 »

If you want to use it at home, just buy 24V PS :)
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Re: Converting a 24V amp to 12V

Post by cb4ever104 »

Those nice people at Zetagi have told me that they only made a 24V of the 501 :) I thought there was a 12V version as well , but they should know :)
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Paul aka "Sammy". (108) PY60 Old Paisley DX Group (RIP Rab Markie)
Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.
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