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    Evolution of Eiclone!

    For joy of tube diy, I re-wired my Eiclone to Kevin Ward's pp KT120 design, but using 7F7 and 7N7 at the front, and no NFB. I love it :banana: With NFB, it produces LF oscillation, whichever value I tried!? From the pic above, the feedback wire is unconnected and coiled up at the top left...
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    Getting The Best Out Of A-431.

    Hi Folks, Built this amp based on Dynaco Mk.3 but uses 5751>12BH7A>GE6550A. It sounds OK but can't come close to my SEUL EF184 driven GEC TT22. I've decided to do a re-built with an all octal base frontal if possible. Anyone out there willing to help out with a proven schematics...
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    Fisher 100AZ - Final Headache!

    Hi Folks! How do you reduce current passing thru EL37 on this amp? Increase cathode resistor R17-A but voltage shoots up... same ! Schematics shows 34v / 240R = 142 mA and mine is 45v / 250R = 180mA. With help from a few honourable members from this Forum, I just managed to tamed the...
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    Fisher 80AZ Rebirth Problem!?

    http://img401.imageshack.us/img401/1136/z6co.jpg Hi Folks ! I've encountered serious problem with my Fisher 100AZ rebuilt. I did almost everything that is needed to remedy the humming and oscillation, screening all the power lines from the OPT. When I first fired it up, it was quite,but...
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    Tango CRD-5 any goodness?

    Hi Folks! Got myself a pair of Tango CRD-5 meant for PP 6CA7. Upon receiving, was disappointed by it's mere size of 3" all round and weighs 1.6kg. Am puzzled by this on right side of tag: Power 15W @ 40% & 23W @ 50% ? Can I do a PP 2a3 with this 5K opt? Any help rendered will be...
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    Seeking HK250 trafo or....

    Hi Folks ... I'm seeking for a single HK250 OPT "FT2382666", to complete my re-built. Anyone out there know where to look for one? Or perhaps, might get a pair of A470 instead! More than two years ago, bought this HK250 thru eBay and was greatly disappointed by one of it's output trafo...
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    HELP!! Regulated PS for #76 Preamp.

    http://img707.imageshack.us/img707/843/regulatedpsfortype76pre.jpg Hi Folks! First off, I'm a newbie and am a retired oil refinery engineer. So, please bear with me, ya? I've built this #76 preamp and feels it's better sounding than my Eico HF85. So, I wish to improve it by using...
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    Baffled by odd figures on D3a ......

    Hi Folks, I'm baffled by the odd readings on the D3a pins of my SEUL KT88. Designed anode voltage is 180v, but I've 168v, 172v, 188v & 193v on the same socket when I roll the four D3a I've. BTW, which tube is the weakest? Care to advice .... thanks! Zekk
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    Ampex 6973 OPT for a beefier amp!?

    Guys ... I've a pair of OPT removed from an Ampex 6973 stereo amp. It's hugh and beleive to be manufactured by Triad. I'm seeking for a schematic where I can ultilise this pair of OPT to build a beefier push-pull amp than the 6973 can project. Can anyone help out? Thanks. Zekk
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    PP 6V6 Built From Thomas Organ Parts!?

    Hi Guys! I'm seeking ideas for a hybrid pp 6V6 built using diodes for power supply. Have a pair of beefy OPT and four gorgeous looking 6V6GT removed from a Thomas organ amp. Motive for this built is that, I'm approaching the end of my life-span and wish to built an amp for my family...
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    Parameter For GEC TT22 ? Pic incl.

    Hi Folks! I'm seeking advices for the best parameter for operating a TT22 in SE mode. Which is better, high voltage/low current or low voltage/ high current? Spec for max: anode is 1200v, g2 is 600v and dissipation is 45 watts. Driver tube is a high GM pentode, EL802 running at 22mA. Anyone...
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    UTC CG-300 Pinouts??

    Hi Folks, Can anyone please help me to figure out the variable primary connections? Pri: 0v, 105v, 115v, 220v, & 230v. Sec: 625v - 515v - 0v -515v -625v. Data sheets does not show pin connection! v Uploaded with ImageShack.us
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    Using 5H choke instead of 10H ??

    Hi Folks! Can any kind folks offer me his thoughts and opinions why a 10H choke should not be swapped with a 5Henries ? I've just bread-boarded a SEUL amp using EL802 to drive TT22. Power supply: 816 > 10H@200mA > 10uf > 10H@200mA > 100uf. Currently, 1st choke is a Parmeko 5H@250mA...
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    5687 Driving KT88 Problem!

    Hi Folks! Can anyone please help-out why my 5687 cannot hold bias voltage steady? Bias dropped from 4v to 1.8v. Plate increase from 215 to 315v. :eek: B+ is 415vdc, 12K loading resistor, plate reads 215v. Cathode reads 4v with a 270R bypass with 470uf. Initially, it was sounding...
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    Ampex 6973 Clone Pics.

    Hi Folks ... I'm back! With pics to fed those picture hungry imates. :D About a year back, I bought a unnamed stereo amp that resembles an Ampex. Beefy OPTs with code: TR159~831839. Beleives it's from a Thomas organ. Chassis strong, but too holee. So, cutted it out and leaves a half...
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    Ampex 6973 Clone!

    Hi Folks! I've just completed clonning an Ampex Signature amp which uses EF86~12AU7~6973. PS consists EZ81~40uf~32K~20uf~39K~10uf. Very nice sounding with tight bass BUT oscillating with a very high pitch tone. Remedy by removing the feedback loop, a 39K bypass with 0.1uf and connected...
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    866A Mercury Rectifier For 811A /A2 !?

    Hi Folks! I love the nice bluish-green glow on this 866A rectifier. Planning to build the SE 811A based on Jim Doyle's design, 6C5~6V6~811A' Question is, besides meeting the requirements for a 2.5v@5A for the filaments, what else should I be cautious off? Can it give a rich glow with a B+ of...
  18. Z

    Beef-up MC-30!?

    I've a pair of refurbished MC-30 sounding gorgeously:music: Enjoy slow rock type of music and obviously needs the extra dynamic, oomph, to drown me like an on-rushing tsunami. So, can anyone reconmend me an approach to beef-up this baby:scratch2:? Thanks for looking & the advices, if any!
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    Oil Can For Tube Amp!

    Hi.. Have anyone try using motor run oil can capacitors in pre or power amp? How do you handle the polarity? Thanks, Zekk
  20. Z

    MC-30 went popping with KT-66!?

    Spent a small fortune on four pieces of Genalex Gold Lion smoked glass to be use on my MC-30 and was greatly disappointed. Fifteen minutes into the music, it produce a periodical popping sound. Thinking that they might be faulty, I bought another quad of re-issue Gold Lion KT-66. Same problem...
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    MC-30 Screw-up!

    Hello Guys! Did a total overhaul of my MC-30 , from nickel platting the chassis to replacing every resistors and capacitors. Eagerly fired it up with a variac without thoroughly check it out. At 65 volts, it started to hum terribly! I immediately cutted off the power supply and to my horror...
  22. Z

    Speaker Wire Resistance?

    Noted that a thicker wire have less resistance than a thinner wire! So, what's the best awg to use for one's high frequency driver? A high resistance or a low resistance wire? :scratch2: Thanks!
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    Biasing Scott 250 Monobloc.

    Hi there! Wondering whether I've wrongly biased the EL34 at 850 mini volts? This Class A runs hot ! Any help will be greatly appreciated. Thanks. Zekk
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    MC-30 Using EL34.

    Hello Folks ... I came across a thread in the Vintage Asylum Forum about using EL34 tubes on MC-30. Must add jumper between pin #1 & #8. Have anyone try that before ?:scratch2: Thanks for looking & Wishing All Members A Even Better New Year Ahead. Zekk
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    Scott 250 Monobloc running hot.

    Hello AK comrades, I've a pair of Scott 250 power amp , 35W Class A, running hot after an hour's playing. Is it normal or can I replace the GE 6CA7 fat boy with something else ? Besides that, it drives my Altec 604-E housed in Billford's designed cab, very musically with deep bass. Thanks...
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