[morzh]

To everyone, especially to Ron or whoever might have the data.

I received the xfmrs.
The output still has 31 ratio which is, I think, wrong, it is supposed to be more like 40.

Now I have a question about the interstage one.

The ratios between the primary and the rest is as follows, primary: secondaries.

To 6L6, both windings, 2:1 (step down).
To tweeters: 13:1 (step down).

Are those correct?

[morzh]

Ron,

Yes we discussed the output one before, and when I sent it back I told them that the 30:1 ratio is wrong and it should be 37:1 to 39:1, and they confirmed they had it wrong and would re-do.
now I am kinda worrying about the interstage. I know they did it for several people, but I am a bit uneasy now that this has happened for the second time.

[morzh]

Ron


You are talking active loss resistances, not impedances. Heyboer did not observe it, theybuse thicker wire.As you might remember, from the Diverted's case, he was worrying about the same exact problem, his DC resistances were way lower which was explained by them using thicker wire, but the actual impedance is only determined by turns ratio, and can't really be derived from the DC ohms shown in the schematic. I have the turns ratio 13:1 which given the 8 ohms of the tweeters would present itself to the 6F6G interstage driver as 1,352 ohms of load. 6F6 wants to see 7K of load asa pentode, or 4K as a triode which I think it is the case here. 1.3K is too low.

[morzh]

I took the old transformer and compared the turns ratio between the tweeter and the 6L6 gate driver wndings. It is exactly the same, 1: 6.52. I cannot confirm the primary as it is open. This gives me hope, though still strange.

The outpyt xfmr is still wrong: they did conform 30:1 ratio that had to change, but it didn't.

[morzh]

Well, reconsider: there is that capacitor, and it is 1uF in the sch, so say at 10kHz the series impedance of it with 8 ohm active is about 18.5 ohm so it reflects as 3,126 ohms which is closer to that 4K the 6F6 triode likes to see. So maybe the Interstage is ok.

Also, the ratio of the DC resistances is also different, in the original the primary to driver windings is 475/260 (in reality the two halves are 273 and 290 ohms) which is 1.8, and the new is 179/69 which is 2.6. But knowing not what gauges are there this, again, means nothing.