Re: Mystery suitcase & unknown chassis
There is indeed a Dac90, minus its case. It's in fairly miserable condition but it still has its o/p transformer and valve and mains dropper.
The car radio is indeed badged DRH - couple if additional pics attached. It has three of its four valves present, but looks like someone has had a go at the front end. The tuning (three presets) is missing its mechanism.
Interesting and surprising to learn that the mystery chassis is likely a Philips PL36 amplifier. I can't see any markings on what (I now assume) will be a push pull output transformer. Last two pics show above and below decks. Assuming four valves, two parallel push pulls that must have been one scary powerful beast.
Last year I built a modest stereo amp around a pair of UL84s, which has created a demand for a repeat from various people including my sister-in-law who liked the steam punk novelty. I was hoping to pull enough components from what remains in the case, but the only pair of o/p valves are ul41, which don't seem to have a great reputation - the case will, however, provide the elusive speaker transformers.
I had a quick look at the PL36 datasets. The graphs show scary high anode currents (over 1000mA!) so I guess this would rule out their single ended use with a conventional SE transformer robbed from one of the other sets. I'm not good at the maths, (so this is from interpretation of the graphs) by under-running the anodes at say 50-70V (I also have a great big toroidal mains TX with a 50V o/p), or by holding down the g2 voltage again to 50 V and biasing g1 high (-30V) or some combination of the above, i wonder if it would be possible to get the anode current down to a suitable range for those little SE output transformers? (and at the same time be on a straight enough bit of the graph to sound ok) It would also have the benefit of keeping the top caps of the anodes down to something safe (ish).
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This isn't intended to be a 'disposals' type thread, but if anyone should see anything they need to maintain the originality of a better example, complete a project etc, send me a PM and I'll send on the bits for postage.
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