I don't know what is available in the Phillipines, but they are available in the US. I don't know it they are new production or old stock. Try www.tubesandmore.com
There were a few compactrons being produced in Russia recently, perhaps someone makes sockets.
There were a few compactrons being produced in Russia recently, perhaps someone makes sockets.
McIntosh MC3500
Dear Pete,
I have schematics AND I have two of these beasts in my home system. Actually mine are MI350s which are the Pro versions of the MC3500 (Just had an extra balanced input xfr and the fronts are silver anodized instead of the pale gold.
Let me have your email and I shall send you the schem and pics of my MI350s. These have been rebuilt and major mods done which improved performance.
I keep a stock of 6LQ6 tubes as they are becoming rarer each day
Steve
Dear Pete,
I have schematics AND I have two of these beasts in my home system. Actually mine are MI350s which are the Pro versions of the MC3500 (Just had an extra balanced input xfr and the fronts are silver anodized instead of the pale gold.
Let me have your email and I shall send you the schem and pics of my MI350s. These have been rebuilt and major mods done which improved performance.
I keep a stock of 6LQ6 tubes as they are becoming rarer each day
Steve
MC3500 McIntosh
To the guy who suggested that 6CA7/EL34 would work in the McIntosh MC3500/MI350 amps.................I think not. They do not have the current rating for this design.
Check the specs of the 6LQ6 vs that of the EL34, they are nowhere close.
My MI350s when set at 117v primary and our voltage in Ventura County in CA is typically 124v, these put out close to 500 watts each.
When I rebuilt my MI350s and did final spec checks (Using Audio Precision System One) the actual power outout was 485 watts with THD at the limit which McIntosh set at 0.15%.
The iron is large enough to do rated power at 20Hz within less than 0.1dB.
Sorry but EL34s are simply not up to the task in these amplifiers
Steve
To the guy who suggested that 6CA7/EL34 would work in the McIntosh MC3500/MI350 amps.................I think not. They do not have the current rating for this design.
Check the specs of the 6LQ6 vs that of the EL34, they are nowhere close.
My MI350s when set at 117v primary and our voltage in Ventura County in CA is typically 124v, these put out close to 500 watts each.
When I rebuilt my MI350s and did final spec checks (Using Audio Precision System One) the actual power outout was 485 watts with THD at the limit which McIntosh set at 0.15%.
The iron is large enough to do rated power at 20Hz within less than 0.1dB.
Sorry but EL34s are simply not up to the task in these amplifiers
Steve
tubelab.com said:
I had a CTC-5 "Special" a few years ago and it worked weakly. It was the oogly limed oak fake finish tabletop and I didn't think the set attractive at all despite it's rarity so I traded it off for several 40's B&W sets. I do have a CTC-4 acquired since that I think IS a nice looking piece of furniture and am spending time restoring it, first refinishing the red mahogany cabinet. The 21AXP22 had gone to air (glass metal seal) and I fortunately have acquired a good replacement. My most recent color acquisition is a CTC-7A with a new 21CYP22 CRT in it. The set actually made a stable, locked color picture with sound for about ten minutes as received until the capacitors started to fail like dominos. This set will be worth re-capping and restoring IMO. The CTC-16's and CTC-20's were decent color sets. I have some of each. My best CTC-20 made a fabulous picture until it lost chroma months after a full restoration and chroma board alignment. I suspect the 3.58 xtal has gone south. The 21FJP22 had a severe case of cataracts but was electricall like new. I had to scrape that plastic goop out from behind the faceplate and the front of the CRT, then reattach it with a small airgap filled with dry argon and sealed with a perimeter bead of RTV. The repair was a scary and time consuming process for me (these CRT's are huge vacuum bombs without an imposion band) but turned out like new.
For anyone not familiar with this problem that faces early color TV collectors/restorers, the clear plastic goop that turns opaque from mold growth is just like that soft plastic in the sandwhich which is a car windshield. Imagine trying to separate the two haves of a windshield without breaking the glass, then add several tons of air pressure on just one side to make it more 'fun'.
Re: MC3500 McIntosh
That 'guy' would be me. As I said, my suggestion was based on handwaving engineering as I had not consulted a tube manual. I do know that if you have 'real' 6CA7 tubes you can get 100 watts RMS from a pair since they were designed to handle 700 or so plate volts, like the 807. I wouldn't try that with so called 6CA7's being offered today by folks trying but not apparently that hard like ElectroHarmonix, to make quality vacuum tubes (IME).
Your Mc is one powerful amp alright. The output iron sounds impressive too! Could you drop in 807's and do without 100 of those watts? You'd never hear the difference. Then there are always KT88's or 6550's. Just thinking aloud. I'm not suggesting you redesign your fine, working well enough as-is collectible amplifier just because I have a pet peeve about the competition for TV TUBES . As a lobbyist I have no power.
MOER said:
That 'guy' would be me. As I said, my suggestion was based on handwaving engineering as I had not consulted a tube manual. I do know that if you have 'real' 6CA7 tubes you can get 100 watts RMS from a pair since they were designed to handle 700 or so plate volts, like the 807. I wouldn't try that with so called 6CA7's being offered today by folks trying but not apparently that hard like ElectroHarmonix, to make quality vacuum tubes (IME).
Your Mc is one powerful amp alright. The output iron sounds impressive too! Could you drop in 807's and do without 100 of those watts? You'd never hear the difference. Then there are always KT88's or 6550's. Just thinking aloud. I'm not suggesting you redesign your fine, working well enough as-is collectible amplifier just because I have a pet peeve about the competition for TV TUBES . As a lobbyist I have no power.
Hi, On the general thread -
I've had good results in a SE DC configuration using the Mullard EF55 (!) Although designated 'F' and not 'L',they were designed for use as video amplifiers in the 1940's and have a power (Anode dissipation) rating of 10w or so. Strapped as a triode they produce an excellent watt or so! Has anyone else tried them? and what results please? Reason I tried them is they are very,very cheap (in UK) and fairly plentiful) only slight drawback is B9G Loctal socket.
Regards,
David.
I've had good results in a SE DC configuration using the Mullard EF55 (!) Although designated 'F' and not 'L',they were designed for use as video amplifiers in the 1940's and have a power (Anode dissipation) rating of 10w or so. Strapped as a triode they produce an excellent watt or so! Has anyone else tried them? and what results please? Reason I tried them is they are very,very cheap (in UK) and fairly plentiful) only slight drawback is B9G Loctal socket.
Regards,
David.
nafunga said:
That tube looks quite like the extremely high transconductance metal video power amplifier pentode, octal base 6AG5 (low plate Z and 8.7 watts Pd.) which is pretty much duplicated in the 9 pin miniature, slightly lower Pd 6CL6. I am planning to use the 6AG5 as a driver in my p-SET 6080 amp. The 6CL6 will swing 132 volts P-P output into a 3900 ohm load with 300 VDC supply.and can make about 2.7 watts RMS as a A1 amplifier.
The octal base video tube you are thinking of is the 6AG7. I have a bunch of these, but haven't had the time to experiment with them yet. I have tried the 9 pin 12BY7, which is a newer video output tube. It makes a good driver in triode or pentode mode and was used as a driver by Harmon Kardon and others. 12HL7 and 12GN7 work better, but are not as common.
I don't have the space to collect TV's, so I had to settle for something smaller, radios. I have too many of these for my small house, but I can't say no when someone gives me one.
The last TV that I rebuilt was an Emerson made by RCA in 1955. This was 1969, I put a "modern" (all glass) CRT into it, replaced every cap, and most of the tubes. It was the only color TV in my neighborhood at the time. About 50 people gathered around it during the Apollo mission to the moon that was televised in color.
I have fixed a few Motorola Golden Views for friends though. Be careful with CRT's if you have ever seen one implode you will know what I mean.
I don't have the space to collect TV's, so I had to settle for something smaller, radios. I have too many of these for my small house, but I can't say no when someone gives me one.
The last TV that I rebuilt was an Emerson made by RCA in 1955. This was 1969, I put a "modern" (all glass) CRT into it, replaced every cap, and most of the tubes. It was the only color TV in my neighborhood at the time. About 50 people gathered around it during the Apollo mission to the moon that was televised in color.
I have fixed a few Motorola Golden Views for friends though. Be careful with CRT's if you have ever seen one implode you will know what I mean.
tubelab.com said:
Thanx for catching my typo, that is what I meant.
I find it pretty hard also to say no to treasure. I stopped collecting vintage TV's when I got about 60 or so of the round screen sets. I ran completely out of room. At least I have enough that I could open a real museum.
That Emerson sounds like the second RCA color set if it was '55 and the first 21 incher with the 21AXP22. Very collectible today. TV studios actually used these and the earliest model the CT-100 as control room monitors in the first years of color broadcasting in the US. I don't have their first the CT-100 but I am very fortunate to have the much rarer 15" Westinghouse H840CK15 that beat the RCA CT100 to stores by a full month in March of 1954. My Westinghouse has the RCA experimental progenitor of the 15GP22 in it. It was the very first NTSC color TV receiver that was offered for sale to the public the whole world. What is extra special to me is that my copy was manufactured the exact same month and year that I was born. I was a color baby!
My set with chassis photos may be seen in historical context here about half way down the page. http://www.tvhistory.tv/advertising3.htm BTW, this is a really excellent TV history website, not mine but I have contributed content.I am very aware of the danger of a CRT implosion which is why I was so fearful while removing the laminated faceplate of that big 21" tube even after taking considerable safety percautions. I am fortunate that my care apparently has paid off. I have never experienced a CRT implosion as a handling accident.
I may be off by a year or so, on the Emerson, but this is what I remember. Vertical output was a 6BL7 or 6BX7. Horizontal output was 6CB5. The cabinet was cube shaped about 2.5 feet on a side. It looked good, made of a dark colored wood. There was a seperate stand made of matching wood that supported the box about 1.5 feet above the floor. I believe that the chassis mounted vertically along one side , but I might be confusing this with another TV. After I rebuilt it it played flawlessly until I moved out of my parents house in 1973, and left it behind.
Re: McIntosh MC3500
Hi Steve,
Thanks, I'd like to see those schematics:
basconsultants at aol dot com
I believe this is the amp that the Greatful Dead used for their PA in the 60s or 70s, and as the power section for their custom guitar amps. Their owned, not leased, PA powered Woodstock as I understand it with 27,000 W of MC3500 power IIRC. Everything except the tweeters were stacks of JBL direct radiators with the tweeters being horns IIRC. You probably know all this.
Pete B.
Hi Steve,
Thanks, I'd like to see those schematics:
basconsultants at aol dot com
I believe this is the amp that the Greatful Dead used for their PA in the 60s or 70s, and as the power section for their custom guitar amps. Their owned, not leased, PA powered Woodstock as I understand it with 27,000 W of MC3500 power IIRC. Everything except the tweeters were stacks of JBL direct radiators with the tweeters being horns IIRC. You probably know all this.
Pete B.
MOER said:
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