Hi guys. I have a few things that I would like to use for a new project. Any ideas of what I can do with them?
(3) C-2305 Chokes - 5H @ 100mA, 300Ω, 1.5KV.
(2) RH-1540 Chokes - 15H @ 40mA, 475Ω, 1.07KV
(20+) Transformers - 250-0-250, 3.15-0-3.15, 75mA
(100+) Capacitors - 10uF to 200+uF (300+WV)
(5+) Turret Boards (most are pretty small)
(1) Pre-drilled board (kind of like a breadboard only with drilled holes)
I have tons of other stuff like transistors, resistors, capacitors, inductors, heatsinks, and some transformers (some even military transformers that are in heavy steel enclosures).
I don't have any good amplifier for listening to music, which I love to do!
Thank you; I appreciate any input!
(3) C-2305 Chokes - 5H @ 100mA, 300Ω, 1.5KV.
(2) RH-1540 Chokes - 15H @ 40mA, 475Ω, 1.07KV
(20+) Transformers - 250-0-250, 3.15-0-3.15, 75mA
(100+) Capacitors - 10uF to 200+uF (300+WV)
(5+) Turret Boards (most are pretty small)
(1) Pre-drilled board (kind of like a breadboard only with drilled holes)
I have tons of other stuff like transistors, resistors, capacitors, inductors, heatsinks, and some transformers (some even military transformers that are in heavy steel enclosures).
I don't have any good amplifier for listening to music, which I love to do!
Thank you; I appreciate any input!
My speakers are just okay. Really nothing special: 88dB sensitivity. I am a student that doesn't have much money; but I have a lot of parts.
I also have a few aluminum chassis sitting around.
I can fish around and I may be able to find a higher current transformer. We have a lot of old military stuff.
The goal is to just get something better than my junk receiver from the 1980s.
If I need to use a MOSFET power amp; so be it. It's better than the all-in-one chip amp that the receiver has.
I also have a few aluminum chassis sitting around.
I can fish around and I may be able to find a higher current transformer. We have a lot of old military stuff.
The goal is to just get something better than my junk receiver from the 1980s.
If I need to use a MOSFET power amp; so be it. It's better than the all-in-one chip amp that the receiver has.
Are some (or all) of the power transformers matching? If you have a pair you could do a PP EL84 or 6V6 design....good for somewhere between 6W and 12W or so, depending on triode or UL outputs.
The pair of chokes would work for this also. Do you have any tubes or output transformers?
Edcor XPP series OT's would be a good budget choice, like an XPP10-8-8K ($17/ea) or XPP15-8-8K ($20/ea). Spend the $3/transformer difference to get the 15W......
Do a search here for Gingertube's baby Huey (EL84 UL-12W), Sy's red light District (EL84 Pentode-15W), Eli's El cheapo and Poindexter's 6GK5/6V6 music machine (6V6 triode 6W).
http://www.diyaudio.com/forums/tubes-valves/72536-el84-amp-baby-huey.html
The pair of chokes would work for this also. Do you have any tubes or output transformers?
Edcor XPP series OT's would be a good budget choice, like an XPP10-8-8K ($17/ea) or XPP15-8-8K ($20/ea). Spend the $3/transformer difference to get the 15W......
Do a search here for Gingertube's baby Huey (EL84 UL-12W), Sy's red light District (EL84 Pentode-15W), Eli's El cheapo and Poindexter's 6GK5/6V6 music machine (6V6 triode 6W).
http://www.diyaudio.com/forums/tubes-valves/72536-el84-amp-baby-huey.html
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I have over 10 of the exact same transformer. The 250-0-250 HV and 3.15-0-3.15 Filament. The amperage isn't very high though.
I do not have any tubes, but I may be able to salvage a bunch of output transformers. We have hundreds of misc. transformers sitting around collecting dust.
I don't plan to be BLASTING my music, but I would like something that I can hear well at decent volumes.
I do not have any tubes, but I may be able to salvage a bunch of output transformers. We have hundreds of misc. transformers sitting around collecting dust.
I don't plan to be BLASTING my music, but I would like something that I can hear well at decent volumes.
There are some things I don't understand about that schematic. What are the "bias" blocks in the shematic. You just substitute the blocks with the components in the dotted box?
I never understood what "bias" really is? Does it basically shift the DC offset?
Also, I don't seem to find the input impedance and output impedances of the OT?
I'll fish around to find a pair of OTs tomorrow.
I never understood what "bias" really is? Does it basically shift the DC offset?
Also, I don't seem to find the input impedance and output impedances of the OT?
I'll fish around to find a pair of OTs tomorrow.
To my knowledge; all the ones I saw had a single primary and 4,8,16Ohm secondaries.
Either way; I'll find a pair that has 8-10K primary and 8Ohm secondary.
I would love to be able to use my chokes. I think they look so cool in the enclosed steel.
So basically, it's a DC offset applied to the grid the flow of electronics to the plate is slowed (less attraction to the plate, or less reach the plate) and therefore the tube won't destroy itself?
Either way; I'll find a pair that has 8-10K primary and 8Ohm secondary.
I would love to be able to use my chokes. I think they look so cool in the enclosed steel.
So basically, it's a DC offset applied to the grid the flow of electronics to the plate is slowed (less attraction to the plate, or less reach the plate) and therefore the tube won't destroy itself?
These are good noob designs. Plus can probably use most of the parts you have on hand
RH 807 - Tube Audio ...... RH DESIGN
RH 84 - Tube Audio ...... RH DESIGN
RH 807 - Tube Audio ...... RH DESIGN
RH 84 - Tube Audio ...... RH DESIGN
Fingerboy: Are you aware of the difference between single ended (SE) designs and push pull (PP) designs?
They require different output transformers, among many other things. The stuff I posted is for PP designs, and your power iron is a bit marginal for even a small PP design, could possibly work, though. Quickie's links are SE designs, more easily realized using your power iron but are going to be limited to around 3-8W or so power out depending on the output tube. SE designs need half as many output tubes, so less $$.
Many SE circuits are very simple and make a good first project. SE designs are all class A operation by definition also.
Edcor's budget SE transformers are XSE series and the budget PP transformers are XPP.
They require different output transformers, among many other things. The stuff I posted is for PP designs, and your power iron is a bit marginal for even a small PP design, could possibly work, though. Quickie's links are SE designs, more easily realized using your power iron but are going to be limited to around 3-8W or so power out depending on the output tube. SE designs need half as many output tubes, so less $$.
Many SE circuits are very simple and make a good first project. SE designs are all class A operation by definition also.
Edcor's budget SE transformers are XSE series and the budget PP transformers are XPP.
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I think. PP are Class B? 2 tubes push signals 180deg out of phase and conjoin for a final output? They share the work, which is why the topology is more efficient.
Less money is good for me. At this part of my life; I'd rather just do something rather than wait for the monster build.
I am interested in Quickie22's designs. They look very simple. Would the 250-0-250 transformer be able to replace the 300-0-300 for less power output? I was also considering changing it to a CLCLC filter section since I have 2 identical chokes that would look nice together. I like the whole symmetrical design.
And.. is there any benefit to a tube rectifier? So far, I haven't seen any feasable research to prove it's better. It seems to just consume power and requires an extra 5V winding (which my transformers don't have).
Less money is good for me. At this part of my life; I'd rather just do something rather than wait for the monster build.
I am interested in Quickie22's designs. They look very simple. Would the 250-0-250 transformer be able to replace the 300-0-300 for less power output? I was also considering changing it to a CLCLC filter section since I have 2 identical chokes that would look nice together. I like the whole symmetrical design.
And.. is there any benefit to a tube rectifier? So far, I haven't seen any feasable research to prove it's better. It seems to just consume power and requires an extra 5V winding (which my transformers don't have).
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Those aren't my designs. They are courtesy of Alex Kitic. I have built these amps and find them pretty good, in fact sounding anytime better than any of my pushpull amps.
You could use the 250-0-250 "as is" if you use solid-state rectifiers. If you do that, you can use a larger first cap and CLC design would be enough, you would get a B+ of around 320V with that. CLCLC would drop perhaps a little more voltage. A tube rectifier would drop more voltage than allowed if using a 250-0-250V trans.
rate them at 450V or higher except the cathode capacitor, you can rate that at 16V. I used standard electrolytics for all caps except for the coupling cap and the cathode cap. Coupling will do well with a polypropylene cap (MKP) 450V or higher and the cathode cap, Elna cerafine.
I play this amp direct off my Ipod and it sounds great.
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