I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
Please help if you can.
Thanks,
Dave
: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
: Please help if you can.
:
:Thanks,
:
:Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193
:: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
:: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
:: Please help if you can.
::
::Thanks,
::
::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
I'm downloading the e-mail now.
I also have an Ampex 2012 with a bad speaker transformer. The resistance of the primary is way too low and when I turn the amplifier on a hear a hum. A few minutes later the fuse opens up. There is 68 ohms from B++ where the center tap of the primary attaches to the chassis. I think that windings must be touching the inside of the case. Another 2012 I'm working on has a much higher resistance and it works great. These 2012s seem to have two extra components. Was there a 2012A? There's a 150pf capacitor and resistor connected to pin 6 of the first AF tube. I cannot find that on the schematics I have. Maybe it's in the SAMs Photofact (in TR-6).
Thanks very much,
Dave
:::Hello All,
::: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
::: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
::: Please help if you can.
:::
:::Thanks,
:::
:::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
: I'm downloading the e-mail now.
:I also have an Ampex 2012 with a bad speaker transformer. The resistance of the primary is way too low and when I turn the amplifier on a hear a hum. A few minutes later the fuse opens up. There is 68 ohms from B++ where the center tap of the primary attaches to the chassis. I think that windings must be touching the inside of the case. Another 2012 I'm working on has a much higher resistance and it works great. These 2012s seem to have two extra components. Was there a 2012A? There's a 150pf capacitor and resistor connected to pin 6 of the first AF tube. I cannot find that on the schematics I have. Maybe it's in the SAMs Photofact (in TR-6).
:
:Thanks very much,
:
:Dave
:
::::Hello All,
:::: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
:::: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
:::: Please help if you can.
::::
::::Thanks,
::::
::::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
No problem. Nothing to be sorry about. Thanks very much for the Sams Photofact.
Dave
:Dave, Sorry, I don't have photofact for for the 2012. Paul
:
:: I'm downloading the e-mail now.
::I also have an Ampex 2012 with a bad speaker transformer. The resistance of the primary is way too low and when I turn the amplifier on a hear a hum. A few minutes later the fuse opens up. There is 68 ohms from B++ where the center tap of the primary attaches to the chassis. I think that windings must be touching the inside of the case. Another 2012 I'm working on has a much higher resistance and it works great. These 2012s seem to have two extra components. Was there a 2012A? There's a 150pf capacitor and resistor connected to pin 6 of the first AF tube. I cannot find that on the schematics I have. Maybe it's in the SAMs Photofact (in TR-6).
::
::Thanks very much,
::
::Dave
::
:::::Hello All,
::::: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
::::: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
::::: Please help if you can.
:::::
:::::Thanks,
:::::
:::::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
No problem. Nothing to be sorry about. Thanks very much for the Sams Photofact.
Dave
:Dave, Sorry, I don't have photofact for for the 2012. Paul
:
:: I'm downloading the e-mail now.
::I also have an Ampex 2012 with a bad speaker transformer. The resistance of the primary is way too low and when I turn the amplifier on a hear a hum. A few minutes later the fuse opens up. There is 68 ohms from B++ where the center tap of the primary attaches to the chassis. I think that windings must be touching the inside of the case. Another 2012 I'm working on has a much higher resistance and it works great. These 2012s seem to have two extra components. Was there a 2012A? There's a 150pf capacitor and resistor connected to pin 6 of the first AF tube. I cannot find that on the schematics I have. Maybe it's in the SAMs Photofact (in TR-6).
::
::Thanks very much,
::
::Dave
::
:::::Hello All,
::::: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
::::: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
::::: Please help if you can.
:::::
:::::Thanks,
:::::
:::::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
I have TR-6 if you need a copy of the schematic. Ampex amplifier 2012 was part of their tape deck 1250 or 1260. The output transformer primary should measure 150Ù DC resistance either side of the B+ tap, primary impedance is 9000Ù C.T. This schematic shows the 150mmf capacitor and a 4700Ù paralleling the 220k plate resistor on pin 6 of the 1st AF amp (EF86).
Meade
:Paul,
: I'm downloading the e-mail now.
:I also have an Ampex 2012 with a bad speaker transformer. The resistance of the primary is way too low and when I turn the amplifier on a hear a hum. A few minutes later the fuse opens up. There is 68 ohms from B++ where the center tap of the primary attaches to the chassis. I think that windings must be touching the inside of the case. Another 2012 I'm working on has a much higher resistance and it works great. These 2012s seem to have two extra components. Was there a 2012A? There's a 150pf capacitor and resistor connected to pin 6 of the first AF tube. I cannot find that on the schematics I have. Maybe it's in the SAMs Photofact (in TR-6).
:
:Thanks very much,
:
:Dave
:
::::Hello All,
:::: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
:::: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
:::: Please help if you can.
::::
::::Thanks,
::::
::::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
:I have TR-6 if you need a copy of the schematic. Ampex amplifier 2012 was part of their tape deck 1250 or 1260. The output transformer primary should measure 150Ù DC resistance either side of the B+ tap, primary impedance is 9000Ù C.T. This schematic shows the 150mmf capacitor and a 4700Ù paralleling the 220k plate resistor on pin 6 of the 1st AF amp (EF86).
:Meade
:
Sorry, "Ω" should have registered as "ohms" Meade
:
:
::Paul,
:: I'm downloading the e-mail now.
::I also have an Ampex 2012 with a bad speaker transformer. The resistance of the primary is way too low and when I turn the amplifier on a hear a hum. A few minutes later the fuse opens up. There is 68 ohms from B++ where the center tap of the primary attaches to the chassis. I think that windings must be touching the inside of the case. Another 2012 I'm working on has a much higher resistance and it works great. These 2012s seem to have two extra components. Was there a 2012A? There's a 150pf capacitor and resistor connected to pin 6 of the first AF tube. I cannot find that on the schematics I have. Maybe it's in the SAMs Photofact (in TR-6).
::
::Thanks very much,
::
::Dave
::
:::::Hello All,
::::: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
::::: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
::::: Please help if you can.
:::::
:::::Thanks,
:::::
:::::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
I just noticed your reply. Yes, I would like the service data for this amplifier. It needs a new speaker transformer. I have another 2012 that is working. Something must have happened to this speaker transformer in this one because the resistances are way too low in this one. If the amplifier is left on in this state, the fuse opens because it's drawing too much current. Maybe one of the Hammonds will work as a replacement.
Thanks very much,
Dave
::Hi Dave,
::I have TR-6 if you need a copy of the schematic. Ampex amplifier 2012 was part of their tape deck 1250 or 1260. The output transformer primary should measure 150Ù DC resistance either side of the B+ tap, primary impedance is 9000Ù C.T. This schematic shows the 150mmf capacitor and a 4700Ù paralleling the 220k plate resistor on pin 6 of the 1st AF amp (EF86).
::Meade
::
:Sorry, "Ω" should have registered as "ohms" Meade
::
::
:::Paul,
::: I'm downloading the e-mail now.
:::I also have an Ampex 2012 with a bad speaker transformer. The resistance of the primary is way too low and when I turn the amplifier on a hear a hum. A few minutes later the fuse opens up. There is 68 ohms from B++ where the center tap of the primary attaches to the chassis. I think that windings must be touching the inside of the case. Another 2012 I'm working on has a much higher resistance and it works great. These 2012s seem to have two extra components. Was there a 2012A? There's a 150pf capacitor and resistor connected to pin 6 of the first AF tube. I cannot find that on the schematics I have. Maybe it's in the SAMs Photofact (in TR-6).
:::
:::Thanks very much,
:::
:::Dave
:::
::::::Hello All,
:::::: I'm working on an Ampex A692 Amplifier with an "egg-cooker" power transformer. It really overheats. There is a part number on it "G.T.C. 1193". Is this an Ampex part number or was this made by a company named G. T. C. ? Does anyone have the Sams photofact (382-5)? It would tell us who made the original power transformer.
:::::: All the paper and electrolytic capacitors have been replaced in this amplifier. The sound is excellent. However, I cannot operate it very long with the transformer in this condition.
:::::: Please help if you can.
::::::
::::::Thanks,
::::::
::::::Dave Hi Dave Ampex part no. B-9402 or alternate no. H-1193 Dave, I scanned the photofact and sent it out in four emails (24 pages) good luck I hope this helps. Paul
Hey ! I had one of those back in the 60's. . . . .and at that time, I thought that it was THE, Criterion against which to judge recorders.
Note that the amps front end design is direct DC coupled and they throttled back on the high freq response with that series RC filer network that you found (in boxed yellow), with it kicking in and suppressing the above ~22 Kc response.
I also placed the AF out transformer data up at the very top and looks like you might have to settle for a more common 10KΩ CT primary and opt either for then using the seconday's 16 Ω in favoring a bit more bass output or the 8 Ω, with it giving a bit less bass output.
Now its schema . . .as per. . . . Jamie Farr . . . .on . . . .In living color. . . . .
BAMMMMMMM ! ! !
AMPEX 2012 Schematic:
73's de Edd
What is the difference between the A692 and the 2012? Other than the speaker terminals being on opposite sides of the chassis, I cannot see any difference at all.
Thanks very much,
Dave
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:Hey ! I had one of those back in the 60's. . . . .and at that time, I thought that it was THE, Criterion against which to judge recorders.
:
:Note that the amps front end design is direct DC coupled and they throttled back on the high freq response with that series RC filer network that you found (in boxed yellow), with it kicking in and suppressing the above ~22 Kc response.
:
:
:
:I also placed the AF out transformer data up at the very top and looks like you might have to settle for a more common 10KΩ CT primary and opt either for then using the seconday's 16 Ω in favoring a bit more bass output or the 8 Ω, with it giving a bit less bass output.
:
:
:
:Now its schema . . .as per. . . . Jamie Farr . . . .on . . . .In living color. . . . .
:
:BAMMMMMMM ! ! !
:
:
:AMPEX 2012 Schematic:
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:73's de Edd
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What is the Power output of these amplifiers? I am guessing 12 watts.
Thanks,
Dave
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:Hey ! I had one of those back in the 60's. . . . .and at that time, I thought that it was THE, Criterion against which to judge recorders.
:
:Note that the amps front end design is direct DC coupled and they throttled back on the high freq response with that series RC filer network that you found (in boxed yellow), with it kicking in and suppressing the above ~22 Kc response.
:
:
:
:I also placed the AF out transformer data up at the very top and looks like you might have to settle for a more common 10KΩ CT primary and opt either for then using the seconday's 16 Ω in favoring a bit more bass output or the 8 Ω, with it giving a bit less bass output.
:
:
:
:Now its schema . . .as per. . . . Jamie Farr . . . .on . . . .In living color. . . . .
:
:BAMMMMMMM ! ! !
:
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:AMPEX 2012 Schematic:
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:73's de Edd
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Certainly sounds right in that ball park,. . .10-12. . . considering the P/P output tubes used, as well as their B+ supply level.
I used mine up, to the point where I got a new STEEE-ROW model of Roberts / Akai.
I got appreciably more “munny” for the AMPEX than I paid for it since it was acquired as a nonworking unit, owned by an associate,
non- techno- oriented collegiate professor, he went to a Tandberg. . . .poor fool.
73's de Edd