Hey Andy, it seems everyone uses a 10Y but never a 10.
What mystical property other than a Micanol base does the 10Y bring
to the party other than OK to use as a class C Oscillator to 10 MHz?
Or is it simply appearance & perhaps a modicum of bragging rights? 😀
I've also seen many 5R4WGB rectifiers used here on DIY. For audio a poor choice,
in my opinion, the forward drop is the largest of this class. But useful to 10,000 feet
should we take it to Gobi Desert. And go to 40,000 at lower voltages.
I gave most all of mine away.👍
What mystical property other than a Micanol base does the 10Y bring
to the party other than OK to use as a class C Oscillator to 10 MHz?
Or is it simply appearance & perhaps a modicum of bragging rights? 😀
I've also seen many 5R4WGB rectifiers used here on DIY. For audio a poor choice,
in my opinion, the forward drop is the largest of this class. But useful to 10,000 feet
should we take it to Gobi Desert. And go to 40,000 at lower voltages.
I gave most all of mine away.👍
10Y is more common. Unlike 10, which was consumer grade tube for AC-powered radios, 10Y is designated RF. Military stocked-up on them, that's why they are relatively plentiful.
Looking at them and see no difference. Both RCA. Actually, one has filament on whiskers, and the other on springs.
Looking at them and see no difference. Both RCA. Actually, one has filament on whiskers, and the other on springs.
Same here - I had a stack of them which I sold. They only fetched low prices, nobody seems interested. The go-to choice is the 5U4 which is a much better tube, or a 5Z3 which as far as I can tell is the same tube with a 4 pin base and usually a lot cheaper.
I am particularly interested in interstage schematics as I bought a set of Monolith Magnetics SA9 OPTs and IT transformers from a fellow forum member here. Having recently bought more efficient speakers I am now pursuing a class A SIT amp on the one hand (almost finished) and would also like to try out a 2A3 or similar as another highly interesting option.
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Which Monolith ITs?
You'll see the Lundahl LL1660 come up in quite a few schematics but I don't think it's much more than "OK". It would be good to hear of some better choices. With sensitive speakers I guess you're looking at around 1:3 step-up? Or are you thinking 1:1 with a SUT?
Making step-up interstage (with few ten mA primary current) isn't general.
It's no coincidence that most of common IT are 1:1 ratio.
Any, if you like 10Y sound, try once graphite anode 801.
I have several 10, 10Y, 801a, but graphite anode 801 is "other category" in tonality.
It's no coincidence that most of common IT are 1:1 ratio.
Any, if you like 10Y sound, try once graphite anode 801.
I have several 10, 10Y, 801a, but graphite anode 801 is "other category" in tonality.
Very much looking forward to seeing your introduction to this project in this forum!
Going back to the 124B for a moment, the FR doesn't look bad at low frequencies despite the 150hz-15K data. It's the HF that's down. It's a beefy transformer rated 5W, 65H inductance. I'm wondering if it could even make a 1:3 interstage to a PP output given its CT on the secondary.
-4 dB at 20K is not bad. But this is with 10K source. With lower impedance source, HF response may be better.
This transformer may work as interstage, but it will need parafeed connection
Andy, just to clarify . . . you're using the Hammond 124B as a SUT in both versions?
Yes - I only have the 124B. I'm waiting for a 1140-LN-C in the next week. Needs to be ordered from Canada.
If the output is 5W, the input must not be lower than 5W. According to this, the primary will allow the input voltage not lower than 223Vrms. Do you think it is possible for such a small transformer?
Perhaps the output 5W is only above 150Hz, and as the frequency decreases, the output power will decrease rapidly....
But if you see the frequency response I posted from the Hammond site it's almost flat down to 40hz. The data doesn't seem to agree with the FR. But yes, 5W seems rather fanciful.
Nothing fanciful about 5 W at 120 Hz. 10 W 60 Hz wall-wart transformers are smaller in size.
Also, no controversy in low frequency response, which was measured at much lower power than 5 W.
All it goes to show is that transformer specs should not be regarded as something absolute: they may change quite dramatically by the operating conditions (source impedance, signal level, termination). A reputable manufacturer like Hammond specifies under what conditions the characteristics were measured, so that a user can figure how the transformer will behave under his/her operating conditions.
Also, no controversy in low frequency response, which was measured at much lower power than 5 W.
All it goes to show is that transformer specs should not be regarded as something absolute: they may change quite dramatically by the operating conditions (source impedance, signal level, termination). A reputable manufacturer like Hammond specifies under what conditions the characteristics were measured, so that a user can figure how the transformer will behave under his/her operating conditions.
