I recently finished restoration on a Zenith 6D512. http://www.nostalgiaair.org/Resources/090/M0025090.htm
All capacitors except the Mica caps were replaced. All the plastic covered wires were replaced (hardened and crumbling) one by one and compared to a second set. One out of tolerance resistor was replaced. A couple of tubes were replaced and all test good. The wire wound antenna was checked and the wire wraps were touching in a couple of places so I separated them and secured with a small dab of rubber glue (originally held with tar). The tuning condensor was removed and cleaned. Checked for shorts/fin interference then reinstalled. I ran it for a while and it had pretty good reception on BC. Short wave was a bit weak but I figured alignment would cure that. I aligned the set and it worked pretty well. The alighment went according to plan and the adjustments did make a difference during the process. Reception seemed pretty good post alignment during a short test and in the basement on Short Wave it was better (but still a little weak). I can provide the process I used to align it if needed.
I played it off and on over a couple of days to shake out any issues. Reception seemed to drop off so I stepped back for a break to get a fresh start. I played around with the case and made sure the chassis fit well/aligned with the dial, knobs etc.
A couple of days later I went back to the set and now it barely picks up AM stations. I removed the chassis from the case and attached a short wire to the antenna connection A (with or without disconnecting the jumper between terminals A&B on antenna) I get reception. Not as strong as I would like but better than without. I double checked all solder connections and they are good. I retested all tubes.
Anyway I am looking for some ideas on what to check first. I am too close to the forest to see the trees right now and any help would be greatly appreciated.
I was thinking of
1. Checking all voltages and
2. Replacing all the Mica Caps including C2 (note there are two) as a start.
Jeff
:
Hi Jeff,
Doug's advice is good. Check your voltages. Pay special attention to the filament voltages on the tubes. You have two 35 volt tubes and four 12 volt tubes. If any have shorted filaments, but not completely shorted, they will have good emission in the tube tester, but poor emission in the radio.
If that doesn't show a problem, pay special attention to grid voltages.
By the way does this radio have any of the rare 12SA7G, 35L6G or 35Z5G tubes in it?
Best Regards,
Bill Grimm
First let me say thank you for the help! Yes Bill, it has those "rare" tubes.
I took Dougs advice and started with the voltage check. I think I have something that may point us un the right direction.
All were mesaured from -B to pin.
35Z5 Pin No.and readings in DC unless noted as VAC
1 = Blank
2 = 121.5 VAC
3 = 116.7 VAC
4 = Blank
5 = 115.2 VAC
6 = Blank
7 = 87.6 AC
8 = 121.4
12SQ7 Pin No and readings in DC unless noted
1 = -1.02
2 = 0.00
3 = 0.00
4 = -0.498
5 + -0/998
6 = 60
7 = 13.86 VAC
8 =0.001
12SA7 Pin No.and readings in DC unless noted as VAC
1 = -1.02
2 = 51.8 VAC
3 = 89.9
4 = 90.1
5 = 0.001
Ground lug = -1.02
6 = Blank
7 = 39.1 VAC
8 = 0.00
14H7 Pin No.and readings in DC unless noted as VAC
1 = 39 VAC
2 = 70.3
3 = 90.1
4 = 0.01
5 = -1.02
6 = -1.0 *** when connecting + lead reception was very strong.
7 = 0.00
8 = 27.2 VAC
12SA7 Pin No.and readings in DC unless noted as VAC
1 = -1.02
2 = 27.3 VAC
3 = 0.6 VAC * Reception increases when + lead contacts
4 = 90.1
5 = -6.6
7 = 0.09
8 = -0.41 * Reception increases when + lead contacts
I haven't tried to analyze yet but there are some incorrect voltages in several places.
Jeff
::Check all voltages first - that's the initial step in troubleshooting. Don't start replacing parts until you get the problem area pinpointed.
::
:Hi Jeff,
:
: Doug's advice is good. Check your voltages. Pay special attention to the filament voltages on the tubes. You have two 35 volt tubes and four 12 volt tubes. If any have shorted filaments, but not completely shorted, they will have good emission in the tube tester, but poor emission in the radio.
: If that doesn't show a problem, pay special attention to grid voltages.
:
: By the way does this radio have any of the rare 12SA7G, 35L6G or 35Z5G tubes in it?
:
:Best Regards,
:
:Bill Grimm
:
:
Hi Jeff,
Doug's advice is good. Check your voltages. Pay special attention to the filament voltages on the tubes. You have two 35 volt tubes and four 12 volt tubes. If any have shorted filaments, but not completely shorted, they will have good emission in the tube tester, but poor emission in the radio.
If that doesn't show a problem, pay special attention to grid voltages.
By the way does this radio have any of the rare 12SA7G, 35L6G or 35Z5G tubes in it?
Best Regards,
Bill Grimm
35Z5 Pin No.and readings in DC unless noted as VAC
Measured Should Be
1 = Blank
2 = 121.5 VAC 117
3 = 116.7 VAC 110
4 = Blank
5 = 115.2 VAC 100
6 = Blank
7 = 87.6 AC 85
8 = 121.4 117
12SQ7 Pin No. and readings in DC unless noted as VAC
Measured Should Be
1 = -1.02 0
2 = 0.00 -0.45
3 = 0.00 0
4 = -0.498 -0.45
5 = -0.498 -0.45
6 = 60 57
7 = 13.86 VAC 115 VAC
8 = 0.001 0
12K7 Pin No.and readings in DC unless noted as VAC
Measured Should Be
1 = -1.02 0
2 = 51.8 VAC 46 VAC
3 = 89.9 85.5
4 = 90.1 86
5 = 0.001 0
Ground lug = -1.02 -0.75
6 = Blank
7 = 39.1 35 AC
8 = 0.00 0
14H7 Pin No.and readings in DC unless noted as VAC
Measured Should Be
1 = 39 VAC 55 VAC
2 = 70.3 56
3 = 90.1 85
4 = 0.01 0
5 = -1.02 0
6 = -1.0 0 * when connecting + lead reception was very strong.
7 = 0.00 -0.75
8 = 27.2 VAC 23 VAC
12SA7 Pin No.and readings in DC unless noted as VAC
Measured Should Be
1 = -1.02 0
2 = 27.3 VAC 23 VAC
3 = 0.6 VAC 85.5 VAC * Reception increases when + lead contacts
4 = 90.1 86
5 = -6.6 0.05
7 = 0.09 11.5
8 = -0.41 0 * Reception increases when + lead contacts
:Check all voltages first - that's the initial step in troubleshooting. Don't start replacing parts until you get the problem area pinpointed.
:
:
:35Z5 Pin No.and readings in DC unless noted as VAC
:Measured Should Be
:1 = Blank
:2 = 121.5 VAC 117
:3 = 116.7 VAC 110
:4 = Blank
:5 = 115.2 VAC 100
:6 = Blank
:7 = 87.6 AC 85
:8 = 121.4 117
:
:12SQ7 Pin No. and readings in DC unless noted as VAC
:Measured Should Be
:1 = -1.02 0
:2 = 0.00 -0.45
:3 = 0.00 0
:4 = -0.498 -0.45
:5 = -0.498 -0.45
:6 = 60 57
:7 = 13.86 VAC 115 VAC
:8 = 0.001 0
:
:12K7 Pin No.and readings in DC unless noted as VAC
:Measured Should Be
:1 = -1.02 0
:2 = 51.8 VAC 46 VAC
:3 = 89.9 85.5
:4 = 90.1 86
:5 = 0.001 0
:Ground lug = -1.02 -0.75
:6 = Blank
:7 = 39.1 35 AC
:8 = 0.00 0
:
:14H7 Pin No.and readings in DC unless noted as VAC
:Measured Should Be
:1 = 39 VAC 55 VAC
:2 = 70.3 56
:3 = 90.1 85
:4 = 0.01 0
:5 = -1.02 0
:6 = -1.0 0 * when connecting + lead reception was very strong.
:7 = 0.00 -0.75
:8 = 27.2 VAC 23 VAC
:
:12SA7 Pin No.and readings in DC unless noted as VAC
:Measured Should Be
:1 = -1.02 0
:2 = 27.3 VAC 23 VAC
:3 = 0.6 VAC 85.5 VAC * Reception increases when + lead contacts
:4 = 90.1 86
:5 = -6.6 0.05
:7 = 0.09 11.5
:8 = -0.41 0 * Reception increases when + lead contacts
:
:
::Check all voltages first - that's the initial step in troubleshooting. Don't start replacing parts until you get the problem area pinpointed.
::
:
Hi Jeff,
Forget the hypothesis about tube filaments. The Recption imrovement caused by several of your readings indicates front end problems.
You may really need one of those coils you ordered. More likely is a bad silver mica or just a new alignment.
Best Regards,
Bill
I remeasured everything and posted below. I do have low voltage on pins 7 ( H is at .09 should be 11.5) and 5 (G is at -6.6 should be +8.5) of the 12SA7. I am not sure what is pulling the 7 voltage down. The voltage is correct at the 12SQ7 pin 7 (H). (H is the filament right? I mistakenly referenced it as the plate below).
Jeff
::Correction to Voltage Readings Sorry I had a dyslexic moment there so I made a spreadsheet:
::
::35Z5 Pin No.and readings in DC unless noted as VAC
::Measured Should Be
::1 = Blank
::2 = 121.5 VAC 117
::3 = 116.7 VAC 110
::4 = Blank
::5 = 115.2 VAC 100
::6 = Blank
::7 = 87.6 AC 85
::8 = 121.4 117
::
::12SQ7 Pin No. and readings in DC unless noted as VAC
::Measured Should Be
::1 = -1.02 0
::2 = 0.00 -0.45
::3 = 0.00 0
::4 = -0.498 -0.45
::5 = -0.498 -0.45
::6 = 60 57
::7 = 13.86 VAC 115 VAC
::8 = 0.001 0
::
::12K7 Pin No.and readings in DC unless noted as VAC
::Measured Should Be
::1 = -1.02 0
::2 = 51.8 VAC 46 VAC
::3 = 89.9 85.5
::4 = 90.1 86
::5 = 0.001 0
::Ground lug = -1.02 -0.75
::6 = Blank
::7 = 39.1 35 AC
::8 = 0.00 0
::
::14H7 Pin No.and readings in DC unless noted as VAC
::Measured Should Be
::1 = 39 VAC 55 VAC
::2 = 70.3 56
::3 = 90.1 85
::4 = 0.01 0
::5 = -1.02 0
::6 = -1.0 0 * when connecting + lead reception was very strong.
::7 = 0.00 -0.75
::8 = 27.2 VAC 23 VAC
::
::12SA7 Pin No.and readings in DC unless noted as VAC
::Measured Should Be
::1 = -1.02 0
::2 = 27.3 VAC 23 VAC
::3 = 0.6 VAC 85.5 VAC * Reception increases when + lead contacts
::4 = 90.1 86
::5 = -6.6 0.05
::7 = 0.09 11.5
::8 = -0.41 0 * Reception increases when + lead contacts
::
::
:::Check all voltages first - that's the initial step in troubleshooting. Don't start replacing parts until you get the problem area pinpointed.
:::
::
:Hi Jeff,
: Forget the hypothesis about tube filaments. The Recption imrovement caused by several of your readings indicates front end problems.
: You may really need one of those coils you ordered. More likely is a bad silver mica or just a new alignment.
:
:Best Regards,
:
:Bill
:
:
:I recently finished restoration on a Zenith 6D512. http://www.nostalgiaair.org/Resources/090/M0025090.htm
:All capacitors except the Mica caps were replaced. All the plastic covered wires were replaced (hardened and crumbling) one by one and compared to a second set. One out of tolerance resistor was replaced. A couple of tubes were replaced and all test good. The wire wound antenna was checked and the wire wraps were touching in a couple of places so I separated them and secured with a small dab of rubber glue (originally held with tar). The tuning condensor was removed and cleaned. Checked for shorts/fin interference then reinstalled. I ran it for a while and it had pretty good reception on BC. Short wave was a bit weak but I figured alignment would cure that. I aligned the set and it worked pretty well. The alighment went according to plan and the adjustments did make a difference during the process. Reception seemed pretty good post alignment during a short test and in the basement on Short Wave it was better (but still a little weak). I can provide the process I used to align it if needed.
:
:I played it off and on over a couple of days to shake out any issues. Reception seemed to drop off so I stepped back for a break to get a fresh start. I played around with the case and made sure the chassis fit well/aligned with the dial, knobs etc.
:
:A couple of days later I went back to the set and now it barely picks up AM stations. I removed the chassis from the case and attached a short wire to the antenna connection A (with or without disconnecting the jumper between terminals A&B on antenna) I get reception. Not as strong as I would like but better than without. I double checked all solder connections and they are good. I retested all tubes.
:
:Anyway I am looking for some ideas on what to check first. I am too close to the forest to see the trees right now and any help would be greatly appreciated.
:
:I was thinking of
:1. Checking all voltages and
:2. Replacing all the Mica Caps including C2 (note there are two) as a start.
:
:Jeff
:
I have run into situations where after playing for a while, a shorted turn manifested itself in the antenna coil, or in one of the I F transformers. I would work backwards with a signal genrator (alignment) starting with the last IF transformer back through stages to the antenna coil.
Ed M
::Hello NA Team,
::
::I recently finished restoration on a Zenith 6D512. http://www.nostalgiaair.org/Resources/090/M0025090.htm
::All capacitors except the Mica caps were replaced. All the plastic covered wires were replaced (hardened and crumbling) one by one and compared to a second set. One out of tolerance resistor was replaced. A couple of tubes were replaced and all test good. The wire wound antenna was checked and the wire wraps were touching in a couple of places so I separated them and secured with a small dab of rubber glue (originally held with tar). The tuning condensor was removed and cleaned. Checked for shorts/fin interference then reinstalled. I ran it for a while and it had pretty good reception on BC. Short wave was a bit weak but I figured alignment would cure that. I aligned the set and it worked pretty well. The alighment went according to plan and the adjustments did make a difference during the process. Reception seemed pretty good post alignment during a short test and in the basement on Short Wave it was better (but still a little weak). I can provide the process I used to align it if needed.
::
::I played it off and on over a couple of days to shake out any issues. Reception seemed to drop off so I stepped back for a break to get a fresh start. I played around with the case and made sure the chassis fit well/aligned with the dial, knobs etc.
::
::A couple of days later I went back to the set and now it barely picks up AM stations. I removed the chassis from the case and attached a short wire to the antenna connection A (with or without disconnecting the jumper between terminals A&B on antenna) I get reception. Not as strong as I would like but better than without. I double checked all solder connections and they are good. I retested all tubes.
::
::Anyway I am looking for some ideas on what to check first. I am too close to the forest to see the trees right now and any help would be greatly appreciated.
::
::I was thinking of
::1. Checking all voltages and
::2. Replacing all the Mica Caps including C2 (note there are two) as a start.
::
::Jeff
::
:
:
:I have run into situations where after playing for a while, a shorted turn manifested itself in the antenna coil, or in one of the I F transformers. I would work backwards with a signal genrator (alignment) starting with the last IF transformer back through stages to the antenna coil.
:
:Ed M
:
:
 |
:
: : : : : : : :Sir Jeff. . . . . : : : : :I would also lean toward a total realignment of the set also, since by now, the set has been left alone and is in a :completely "dry" state. : :And by that , since I DON'T know if and or what chemicals were involved, I was thinking of a wet chemical getting :into and detuning a tuned circuit. And if it had to seep / creep up into a place by capillary action , it usually takes :awhile to completely dry out from such a situation. UNLESS the situation is KNOWN and hair dryer heat is used to :speed up the drying out process. : :This info is particularly being directed towards a capacitive element, where the capacitance would shift from being in a moist condition, and then incrementally shifting value when going back towards a completely dry condition. : : :Your supplied voltage measurements seemed to not be too far astray, with you only experiencing the gain shift when your metering skewed the AVC voltage. : : :Also I think that I can see that you just merely made an entry error on your 12SQ7 filament voltage, as 12-13 VAC is correct. : : :But some of your other filament voltages . .in the RF section . . . seem to be a bit squirrelly, so cut out any potential ambiguity, by powering up and measuring each individual fil voltage RIGHT across the filament connections of each tube in order to see what voltage each one is REALLY receiving . : : :You just might have problems in that area, with a buggy series tube which is causing filamental supply variants. : : : :ASIDE: : :I also caught your plotting out the nice spacing apart of the two . . . measured/should be . . . voltages, looking fine :when seeing them placed in the naked HTML posting area, but when then converted to the forum post, afterwhich they came out :alljammedtogetherlikethis. : : :To avoid that in the future, you might insert other elements in place of the use of multiple repetetive spaces. : : :E.G. . .below, initially using repetetive spaces ( ignored,after the first space . . and then is alljammedtogetherlikethis), then trying periods, underlines, dashes, all of which are now being acccepted ! : :Test5v10vTest : :Test5v . . . 10vTest : :Test5v____10vTest : :Test5v-----10vTest : :Test5v 10vTest (The most involved, HTML method . . . unless using cut n' paste) : : :OOOOOOPS . .I have to show the LAST HTML example like this below, otherwise it would have been transparent and would not have shown up with the coding required between the 5v and the 10v : : :>Test5v & n b s p & n b s p & n b s p & n b s p & n b s p & n b s p 10vTest< : : : : : : :73's de Edd : : : : |
:
:
EDD:
You remind me of a poem:
In days of old, when lovers met, they met with happy heart.
And when they sat together,
T h e y s a t r e a l f a r a p a r t.
But now today, when lovers meet, they meet with torrid kiss.
And when they sit together,
Theysitrealcloselikethis.
This might be a time for a little freeze-spray. I have found many an intermittent with that stuff. Caution: It will cause ambient water vapor to condense on the component. Use with caution aaround high Voltages.
Lewis
Measured Should Be
1 = Blank
2 = 121.5 VAC 117 H
3 = 116.7 VAC 110 H2
4 = Blank
5 = 115.2 VAC 100 P
6 = Blank
7 = 87.6 AC 85 H
8 = 121.4 117 K
12SQ7
Measured Should Be
1 = -1.02 0 S
2 = 0.00 -0.45 G
3 = 0.00 0 K
4 = -0.498 -0.45 Dp
5 = -0.498 -0.45 Dp
6 = 60 57 P
7 = 13.86 VAC 11.5 VAC H Connects 12SA7 Plate pin 7
8 = 0.001 0 H
12K7
Measured Should Be
1 = -1.02 0 S
2 = 51.8 VAC 46 VAC H
3 = 89.9 85.5 P
4 = 90.1 86 G2
5 = 0.001 0 Su
Ground lug = -1.02 -0.75
6 = Blank
7 = 39.1 35 AC H
8 = 0.00 0 K
14H7
Measured Should Be
1 = 39 VAC 55 VAC H
2 = 70.3 56 P
3 = 90.1 85 Gs
4 = 0.01 0 Su
5 = -1.02 0 ?
6 = -1.0 -0.75 Grid connected + lead reception very strong.
7 = 0.00 0 K
8 = 27.2 VAC 23 VAC Heater
12SA7
Measured Should Be
1 = -1.02 0 S
2 = 27.3 VAC 23 VAC Heater
3 = 90.1 85.5 VAC Plate *Reception increases when + lead contacts
4 = 90.1 86 Gs
5 = -6.6 8.5 Go <<<<<
6= 0.5 0.09 H
7 = 0.09 11.5 H <<< Note: to 12SQ7 Plate pin 7.
8 = -0.41 0 H * Reception increases when + lead contacts
35L6
Measured Should Be
1 = Blank
2 = 51.8 VAC 46 VAC H
3 = 83 79 P
4 = 90.2 86 Gs
5 = 0.001 0 G
6 = Blank
7 = 87.7 VAC 83 VAC H
8 = 27.2 VAC 23 VAC K
Hope all this lines up after posting!
Jeff
::
::
::
::
::
::
::
::
::
::Sir Jeff. . . . .
::
::
::
::
::I would also lean toward a total realignment of the set also, since by now, the set has been left alone and is in a
::completely "dry" state.
::
::And by that , since I DON'T know if and or what chemicals were involved, I was thinking of a wet chemical getting
::into and detuning a tuned circuit. And if it had to seep / creep up into a place by capillary action , it usually takes
::awhile to completely dry out from such a situation. UNLESS the situation is KNOWN and hair dryer heat is used to
::speed up the drying out process.
::
::This info is particularly being directed towards a capacitive element, where the capacitance would shift from being in a moist condition, and then incrementally shifting value when going back towards a completely dry condition.
::
::
::Your supplied voltage measurements seemed to not be too far astray, with you only experiencing the gain shift when your metering skewed the AVC voltage.
::
::
::Also I think that I can see that you just merely made an entry error on your 12SQ7 filament voltage, as 12-13 VAC is correct.
::
::
::But some of your other filament voltages . .in the RF section . . . seem to be a bit squirrelly, so cut out any potential ambiguity, by powering up and measuring each individual fil voltage RIGHT across the filament connections of each tube in order to see what voltage each one is REALLY receiving .
::
::
::You just might have problems in that area, with a buggy series tube which is causing filamental supply variants.
::
::
::
::ASIDE:
::
::I also caught your plotting out the nice spacing apart of the two . . . measured/should be . . . voltages, looking fine
::when seeing them placed in the naked HTML posting area, but when then converted to the forum post, afterwhich they came out
::alljammedtogetherlikethis.
::
::
::To avoid that in the future, you might insert other elements in place of the use of multiple repetetive spaces.
::
::
::E.G. . .below, initially using repetetive spaces ( ignored,after the first space . . and then is alljammedtogetherlikethis), then trying periods, underlines, dashes, all of which are now being acccepted !
::
::Test5v10vTest
::
::Test5v . . . 10vTest
::
::Test5v____10vTest
::
::Test5v-----10vTest
::
::Test5v 10vTest (The most involved, HTML method . . . unless using cut n' paste)
::
::
::OOOOOOPS . .I have to show the LAST HTML example like this below, otherwise it would have been transparent and would not have shown up with the coding required between the 5v and the 10v
::
::
::>Test5v & n b s p & n b s p & n b s p & n b s p & n b s p & n b s p 10vTest<
::
::
::
::
::
::
::73's de Edd
::
::
::
::
::
::
:
:
:
:
:EDD:
:You remind me of a poem:
:
:In days of old, when lovers met, they met with happy heart.
:And when they sat together,
:T h e y s a t r e a l f a r a p a r t.
:
:But now today, when lovers meet, they meet with torrid kiss.
:And when they sit together,
:Theysitrealcloselikethis.
:
:This might be a time for a little freeze-spray. I have found many an intermittent with that stuff. Caution: It will cause ambient water vapor to condense on the component. Use with caution aaround high Voltages.
:Lewis
:
The remaining voltage issue is the low G voltage on pin 5. I made sure to retest that too in case the same oxidation was casuing it. No luck. I get no or very low voltage readings there.
:I took more time and went over my spreadsheet list, retesting every measurement and fixing any errors. One prior measurment was on AC when meter should have been on DC (duh), etc. Here is the final. I now see only 2 or 3 places that the voltage is off <<<<<
:35Z5
:Measured Should Be
:1 = Blank
:2 = 121.5 VAC 117 H
:3 = 116.7 VAC 110 H2
:4 = Blank
:5 = 115.2 VAC 100 P
:6 = Blank
:7 = 87.6 AC 85 H
:8 = 121.4 117 K
:
:12SQ7
:Measured Should Be
:1 = -1.02 0 S
:2 = 0.00 -0.45 G
:3 = 0.00 0 K
:4 = -0.498 -0.45 Dp
:5 = -0.498 -0.45 Dp
:6 = 60 57 P
:7 = 13.86 VAC 11.5 VAC H Connects 12SA7 Plate pin 7
:8 = 0.001 0 H
:
:12K7
:Measured Should Be
:1 = -1.02 0 S
:2 = 51.8 VAC 46 VAC H
:3 = 89.9 85.5 P
:4 = 90.1 86 G2
:5 = 0.001 0 Su
:Ground lug = -1.02 -0.75
:6 = Blank
:7 = 39.1 35 AC H
:8 = 0.00 0 K
:
:14H7
:Measured Should Be
:1 = 39 VAC 55 VAC H
:2 = 70.3 56 P
:3 = 90.1 85 Gs
:4 = 0.01 0 Su
:5 = -1.02 0 ?
:6 = -1.0 -0.75 Grid connected + lead reception very strong.
:7 = 0.00 0 K
:8 = 27.2 VAC 23 VAC Heater
:
:12SA7
:Measured Should Be
:1 = -1.02 0 S
:2 = 27.3 VAC 23 VAC Heater
:3 = 90.1 85.5 VAC Plate *Reception increases when + lead contacts
:4 = 90.1 86 Gs
:5 = -6.6 8.5 Go <<<<<
:6= 0.5 0.09 H
:7 = 0.09 11.5 H <<< Note: to 12SQ7 Plate pin 7.
:8 = -0.41 0 H * Reception increases when + lead contacts
:
:35L6
:Measured Should Be
:1 = Blank
:2 = 51.8 VAC 46 VAC H
:3 = 83 79 P
:4 = 90.2 86 Gs
:5 = 0.001 0 G
:6 = Blank
:7 = 87.7 VAC 83 VAC H
:8 = 27.2 VAC 23 VAC K
:
:
:Hope all this lines up after posting!
:Jeff
:
:
:
:
:
:::
:::
:::
:::
:::
:::
:::
:::
:::
:::Sir Jeff. . . . .
:::
:::
:::
:::
:::I would also lean toward a total realignment of the set also, since by now, the set has been left alone and is in a
:::completely "dry" state.
:::
:::And by that , since I DON'T know if and or what chemicals were involved, I was thinking of a wet chemical getting
:::into and detuning a tuned circuit. And if it had to seep / creep up into a place by capillary action , it usually takes
:::awhile to completely dry out from such a situation. UNLESS the situation is KNOWN and hair dryer heat is used to
:::speed up the drying out process.
:::
:::This info is particularly being directed towards a capacitive element, where the capacitance would shift from being in a moist condition, and then incrementally shifting value when going back towards a completely dry condition.
:::
:::
:::Your supplied voltage measurements seemed to not be too far astray, with you only experiencing the gain shift when your metering skewed the AVC voltage.
:::
:::
:::Also I think that I can see that you just merely made an entry error on your 12SQ7 filament voltage, as 12-13 VAC is correct.
:::
:::
:::But some of your other filament voltages . .in the RF section . . . seem to be a bit squirrelly, so cut out any potential ambiguity, by powering up and measuring each individual fil voltage RIGHT across the filament connections of each tube in order to see what voltage each one is REALLY receiving .
:::
:::
:::You just might have problems in that area, with a buggy series tube which is causing filamental supply variants.
:::
:::
:::
:::ASIDE:
:::
:::I also caught your plotting out the nice spacing apart of the two . . . measured/should be . . . voltages, looking fine
:::when seeing them placed in the naked HTML posting area, but when then converted to the forum post, afterwhich they came out
:::alljammedtogetherlikethis.
:::
:::
:::To avoid that in the future, you might insert other elements in place of the use of multiple repetetive spaces.
:::
:::
:::E.G. . .below, initially using repetetive spaces ( ignored,after the first space . . and then is alljammedtogetherlikethis), then trying periods, underlines, dashes, all of which are now being acccepted !
:::
:::Test5v10vTest
:::
:::Test5v . . . 10vTest
:::
:::Test5v____10vTest
:::
:::Test5v-----10vTest
:::
:::Test5v 10vTest (The most involved, HTML method . . . unless using cut n' paste)
:::
:::
:::OOOOOOPS . .I have to show the LAST HTML example like this below, otherwise it would have been transparent and would not have shown up with the coding required between the 5v and the 10v
:::
:::
:::>Test5v & n b s p & n b s p & n b s p & n b s p & n b s p & n b s p 10vTest<
:::
:::
:::
:::
:::
:::
:::73's de Edd
:::
:::
:::
:::
:::
:::
::
::
::
::
::EDD:
::You remind me of a poem:
::
::In days of old, when lovers met, they met with happy heart.
::And when they sat together,
::T h e y s a t r e a l f a r a p a r t.
::
::But now today, when lovers meet, they meet with torrid kiss.
::And when they sit together,
::Theysitrealcloselikethis.
::
::This might be a time for a little freeze-spray. I have found many an intermittent with that stuff. Caution: It will cause ambient water vapor to condense on the component. Use with caution aaround high Voltages.
::Lewis
::
:
Thank you!
I will definately try a reailgnment as you suggested. I did use a little contact cleaner on the SW AM switch a while back. Just can't remember which day. Sorry about the squeezed together data. It would be easier if I could submit the spreadsheet or preformat first for the site without the need to add all those spaces.
Funny poem!
Jeff
:
:
:
:
:
:
:
:
:
:Sir Jeff. . . . .
:
:
:
:
:I would also lean toward a total realignment of the set also, since by now, the set has been left alone and is in a
:completely "dry" state.
:
:And by that , since I DON'T know if and or what chemicals were involved, I was thinking of a wet chemical getting
:into and detuning a tuned circuit. And if it had to seep / creep up into a place by capillary action , it usually takes
:awhile to completely dry out from such a situation. UNLESS the situation is KNOWN and hair dryer heat is used to
:speed up the drying out process.
:
:This info is particularly being directed towards a capacitive element, where the capacitance would shift from being in a moist condition, and then incrementally shifting value when going back towards a completely dry condition.
:
:
:Your supplied voltage measurements seemed to not be too far astray, with you only experiencing the gain shift when your metering skewed the AVC voltage.
:
:
:Also I think that I can see that you just merely made an entry error on your 12SQ7 filament voltage, as 12-13 VAC is correct.
:
:
:But some of your other filament voltages . .in the RF section . . . seem to be a bit squirrelly, so cut out any potential ambiguity, by powering up and measuring each individual fil voltage RIGHT across the filament connections of each tube in order to see what voltage each one is REALLY receiving .
:
:
:You just might have problems in that area, with a buggy series tube which is causing filamental supply variants.
:
:
:
:ASIDE:
:
:I also caught your plotting out the nice spacing apart of the two . . . measured/should be . . . voltages, looking fine
:when seeing them placed in the naked HTML posting area, but when then converted to the forum post, afterwhich they came out
:alljammedtogetherlikethis.
:
:
:To avoid that in the future, you might insert other elements in place of the use of multiple repetetive spaces.
:
:
:E.G. . .below, initially using repetetive spaces ( ignored,after the first space . . and then is alljammedtogetherlikethis), then trying periods, underlines, dashes, all of which are now being acccepted !
:
:Test5v10vTest
:
:Test5v . . . 10vTest
:
:Test5v____10vTest
:
:Test5v-----10vTest
:
:Test5v 10vTest (The most involved, HTML method . . . unless using cut n' paste)
:
:
:OOOOOOPS . .I have to show the LAST HTML example like this below, otherwise it would have been transparent and would not have shown up with the coding required between the 5v and the 10v
:
:
:>Test5v & n b s p & n b s p & n b s p & n b s p & n b s p & n b s p 10vTest<
:
:
:
:
:
:
:73's de Edd
:
:
:
:
:
: