I think an EL84 would be overkill as a sub for an ELL80. Most of these sets only run about 260 volts dc at the plate and the output transformers aren't particularly large either. And the bigger problem is the heater current, which is 1.5 amp for a pair of EL84 vs .55 amp for an ELL80. I think you would run into difficulties with the power transformer, which in the German radio sets, typically doesn't have a lot of extra current capability to spare. You would probably have to add an external transformer for the heaters.
Maybe wouldn't sound as nice either running at lower voltages. JJ makes a cut down EL84 for lower power uses that might fit the bill though if one wants something in production. Probably would need the added heater trans also. A low cost and fairly small item to add though.
Called the EL-844
Eurotubes - Descriptions of JJ Electronic power and preamp tubes.
Called the EL-844
Eurotubes - Descriptions of JJ Electronic power and preamp tubes.
If I see it correctly, his unit doesn't feature the original power tranny. There's a substitute of unknown specs and a separate fuse holder, which is mounted in the chassis, instead of the original penolic carrier platee. So his tranny might be sufficient enough for various ELL80 subs.
Best regards!
I'm not familiar enough with that particular chassis to know whether the trafo is original or not. It sure looks of German origin to me and the squared off covers are characteristic of these radios. Also keep in mind that this set appears configured for North American markets, in that it has a US style power interlock on the back, and it doesn't appear to have any primary voltage selector switch. It's also not uncommon to see a chassis mounted fuse holder in German sets for N. American export, and that too appears to be a German made one. So, I wouldn't assume the transformer was replaced, and even if it was, the current ability of the present transformer is still an unknown.
Yes, agreed, you're surely right in all points.
I've meant before that you might be lucky to own a set with a power tranny that allows you lots of tweaking, you know
?
Btw, the original look of these sets, prepared for European markets, is this one:
We see the power tranny with no end bells, but with a phenolic board, carrying the fuse holder and the voltage selector, mounted instead.
Another advice: If it shows FM issues, the small electrolytic (5 µF or so) in the ratio demodulator after the last IF tube EBF89 should be replaced.
After all, it is of good design. Have fun with it!
Best regards!
I've meant before that you might be lucky to own a set with a power tranny that allows you lots of tweaking, you know
?Btw, the original look of these sets, prepared for European markets, is this one:
We see the power tranny with no end bells, but with a phenolic board, carrying the fuse holder and the voltage selector, mounted instead.
Another advice: If it shows FM issues, the small electrolytic (5 µF or so) in the ratio demodulator after the last IF tube EBF89 should be replaced.
After all, it is of good design. Have fun with it!
Best regards!
Ok, so I am back from a family visit and had a look at the unit. The caps i am going to change are;
1) mains filter electrolytic - 100 uf 35 volt
2) C1003 / C1303 - 0.22 mfd 400 volt
3) C1004 / C1304 - 3300 pf 500 volt
4) C1102/ C1402 - .01 mfd 125 volt
5) C1103 / C1403 - 220 pf 400 volt
there is also a large green one near the ELL80 - C1209 - 8 uf 385 volt
Am I missing anything obvious? Also, I have never ordered caps before. There is a local electrical supplies shop. Would that be the best place for such a small order or should i go to mousers.com? Mousers total cost is under $20
1) mains filter electrolytic - 100 uf 35 volt
2) C1003 / C1303 - 0.22 mfd 400 volt
3) C1004 / C1304 - 3300 pf 500 volt
4) C1102/ C1402 - .01 mfd 125 volt
5) C1103 / C1403 - 220 pf 400 volt
there is also a large green one near the ELL80 - C1209 - 8 uf 385 volt
Am I missing anything obvious? Also, I have never ordered caps before. There is a local electrical supplies shop. Would that be the best place for such a small order or should i go to mousers.com? Mousers total cost is under $20
Agreed with the mains filter electrolytic. The other ones only should be replaced if they were paper caps. Issues with foil caps aren't that usual. The 8 µF electrolytic probably is the ELL80s' screen filter cap - replace it.
Best regards!
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