Help with I.D.

I was digging through the pile and came across these as potential donor heat sinks but then saw HCA and started having fantasies about old Parasound amps. I thought they might be Rauland but no. I looked up the silicon and if I interpret correctly these are indeed high current modules, albeit '83 TO-3 stuff. I'm a big ol' electron dummy and not afraid of asking for help. These appear to be slide-in modules for a large chassis. Just curious before I strip them out.
 

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They are alright: good complementary PP assemblies. You can reuse them in any conventional BJT amplifier. They might not be as sharp as modern alternatives, be they are perfectly OK, and have stood the test of time.
Try to reuse them instead of just cannibalizing them. Just test them and tighten the screws, they are good for another 40 years
 
Thank you for that Elvee. My level of knowledge pales in comparison with most members here but I am trying to learn. My understanding of push-pull is that there is a complimentary pair of transistors (or tubes) that each amplify one half of the waveform. Now I have some industrial strength amps that have the same transistor one after another. Am I correct to assume that this is a single-ended amplifier, or one that flips the bottom half of the waveform to the top? This is my crude understanding of class A operation as opposed to class AB and that this mode of operation eliminates crossover distortion when the signal is handed over between a complimentary pair of output devices and across the waveform base line. If my assumption is correct this pair of amps should make fine air fryers.
 

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I'm curious what it is you need help identifying. You say you've already looked up the devices on the heat sinks and it clearly says Rauland-Borg Corp model TAX250 on the chassis. A quick search reveals this: https://usermanual.wiki/Document/RaulandFax250PowerAmplifier.1522834031.pdf

Now that's the FAX250, not TAX250, but it looks like the two models are pretty similar. It appears to be a PA amplifier.

Tom
 
Hi Tom. The modules in the first post were loose. I was just wondering if anyone recognized them. The Rauland-Borg in the second post is assembled. You are correct that these are PA/fire signaling amps. They include output matching transformers with taps at 8, 30 and 70 ohms.