Mitch
:
:Mitch
:
The 6U5 tube is shorted, dead.
Will the radio work without it if all else is good in the circuits?
Stromberg-Carlson model 230L, schematic here at NA.
Mitch
:Are these tubes interchangeable?
:
:Mitch
:
:
::Are these tubes interchangeable?
::
::Mitch
::
:
:I think that the same amount of AVC Voltage will close the eye somewhat differently, but not enough to really make much difference.
Lewis
http://www.youtube.com/watch?v=QFTDOZz-LlE
Clifton
::According to MagicEyeTubes.com, 6U5 and 6G5 are identical substitutes.
::
:::Are these tubes interchangeable?
:::
:::Mitch
:::
::
::I think that the same amount of AVC Voltage will close the eye somewhat differently, but not enough to really make much difference.
:Lewis
:
:
The information you have been given is correct, they are electrically interchangeable.
Physically they are different. 6G5 is an ST glass tube, like octal tubes with the 'G' suffix.
The 6U5 is an elongated bantam shaped tube, similar to 'GT' suffix octal tubes, although longer.
The 6E5, which you did not ask about has a higher gain triode, so it will close faster on strong stations. This tube exists in both ST glass and bantam with no change in part number. A mistake not repeated with the 6U5/6G5.
The same relationship exists with the 6N5 and 6AB5. 6N5 is ST glass and 6AB5 is bantam. These have lower filament draw and lower plate voltage characteristics than the other eye tubes. They were commonly used in farm radios as tuning indicators.
All the Best,
Bill
: The information you have been given is correct, they are electrically interchangeable.
: Physically they are different. 6G5 is an ST glass tube, like octal tubes with the 'G' suffix.
: The 6U5 is an elongated bantam shaped tube, similar to 'GT' suffix octal tubes, although longer.
:
: The 6E5, which you did not ask about has a higher gain triode, so it will close faster on strong stations. This tube exists in both ST glass and bantam with no change in part number. A mistake not repeated with the 6U5/6G5.
:
: The same relationship exists with the 6N5 and 6AB5. 6N5 is ST glass and 6AB5 is bantam. These have lower filament draw and lower plate voltage characteristics than the other eye tubes. They were commonly used in farm radios as tuning indicators.
:
:All the Best,
:
:Bill
:
Thank you for all of the information.
I am ready to purchase a new eye tube.
The schematic calls for a 6G5 and what I took out that was dead is a 6U5.
I am going to look for a 6G5 to keep the radio original, I will also check the 1 Meg. resistor.
Comments welcome,
Mitch
:: The information you have been given is correct, they are electrically interchangeable.
:: Physically they are different. 6G5 is an ST glass tube, like octal tubes with the 'G' suffix.
:: The 6U5 is an elongated bantam shaped tube, similar to 'GT' suffix octal tubes, although longer.
::
:: The 6E5, which you did not ask about has a higher gain triode, so it will close faster on strong stations. This tube exists in both ST glass and bantam with no change in part number. A mistake not repeated with the 6U5/6G5.
::
:: The same relationship exists with the 6N5 and 6AB5. 6N5 is ST glass and 6AB5 is bantam. These have lower filament draw and lower plate voltage characteristics than the other eye tubes. They were commonly used in farm radios as tuning indicators.
::
::All the Best,
::
::Bill
::
:Thank you for all of the information.
:
:I am ready to purchase a new eye tube.
:
:The schematic calls for a 6G5 and what I took out that was dead is a 6U5.
:
:I am going to look for a 6G5 to keep the radio original, I will also check the 1 Meg. resistor.
:
:Comments welcome,
:
:Mitch
:
Hi Mitch,
Good luck on finding a 6G5 that will be suitable for use. However, you will not likely get it.
6G5 is older than the 6E5 and the last one was made when radio listeners actually replaced them when they went bad. The last one was also made at a time when coating the phosphor hadn't been perfected, so their life span was shorter.
All in all finding a 6G5 that still has good green is a long shot. 6U5 are expensive, too. Last winter I paid $38 for an NOS 6U5.
By the way, the reason that resistor is always bad is due to an engineering error. The resistor is rated as 1/4 watt and the tube causes it to dissipate 1/4 watt, yet it always goes bad.
The problem is that the 1/4 watt rating on the resistor is its rating with air flowing freely around it. In that tube socket it cannot dissipate the 1/4 watt. It overheats and then fails.
All the Best,
Bill G.
::: The information you have been given is correct, they are electrically interchangeable.
::: Physically they are different. 6G5 is an ST glass tube, like octal tubes with the 'G' suffix.
::: The 6U5 is an elongated bantam shaped tube, similar to 'GT' suffix octal tubes, although longer.
:::
::: The 6E5, which you did not ask about has a higher gain triode, so it will close faster on strong stations. This tube exists in both ST glass and bantam with no change in part number. A mistake not repeated with the 6U5/6G5.
:::
::: The same relationship exists with the 6N5 and 6AB5. 6N5 is ST glass and 6AB5 is bantam. These have lower filament draw and lower plate voltage characteristics than the other eye tubes. They were commonly used in farm radios as tuning indicators.
:::
:::All the Best,
:::
:::Bill
:::
::Thank you for all of the information.
::
::I am ready to purchase a new eye tube.
::
::The schematic calls for a 6G5 and what I took out that was dead is a 6U5.
::
::I am going to look for a 6G5 to keep the radio original, I will also check the 1 Meg. resistor.
::
::Comments welcome,
::
::Mitch
::
:Hi Mitch,
: Good luck on finding a 6G5 that will be suitable for use. However, you will not likely get it.
: 6G5 is older than the 6E5 and the last one was made when radio listeners actually replaced them when they went bad. The last one was also made at a time when coating the phosphor hadn't been perfected, so their life span was shorter.
: All in all finding a 6G5 that still has good green is a long shot. 6U5 are expensive, too. Last winter I paid $38 for an NOS 6U5.
:
: By the way, the reason that resistor is always bad is due to an engineering error. The resistor is rated as 1/4 watt and the tube causes it to dissipate 1/4 watt, yet it always goes bad.
: The problem is that the 1/4 watt rating on the resistor is its rating with air flowing freely around it. In that tube socket it cannot dissipate the 1/4 watt. It overheats and then fails.
:
:All the Best,
:
:Bill G.
:
Hello Bill and all,
I did find a 6G5 at www.vacummtubes.net, they had three in stock. I actually called and talked with one of the owners about the quality of the tube. Guaranteed as spelled out on their web site. Money back or another tube.
It is a customers radio and he agreed to pay the $40.00 price of the tube + $7.00 shipping.
Question, I have not found the resistor in the tube socket, must be in the chassis somewhere. Would it be wise to replace it with a 1/2 watt resistor inside the chassis?
Thank you,
Mitch
You got really good luck! They will be sold out of 6G5 before the end of the year selling them at that price, especially now that you posted their web site here. I may go snatch one!
Count the wires coming from the socket. If you only have four, then the resistor was in there, but isn't any more. The resistor goes between pins 2 and 4 of the 6G5.
Best Regards,
Bill
Norm
:Hi Mitch,
: You got really good luck! They will be sold out of 6G5 before the end of the year selling them at that price, especially now that you posted their web site here. I may go snatch one!
:
: Count the wires coming from the socket. If you only have four, then the resistor was in there, but isn't any more. The resistor goes between pins 2 and 4 of the 6G5.
:
:Best Regards,
:
:Bill
:
:
:Norm
:
:
::Hi Mitch,
:: You got really good luck! They will be sold out of 6G5 before the end of the year selling them at that price, especially now that you posted their web site here. I may go snatch one!
::
:: Count the wires coming from the socket. If you only have four, then the resistor was in there, but isn't any more. The resistor goes between pins 2 and 4 of the 6G5.
::
::Best Regards,
::
::Bill
::
:
:
The Tube socket has four wires connected to it. There is absolutely no evidence that a resistor was installed in or on the tube socket. Could the resistor be installed inside the chassis?
Mitch
If not you do need a 1 Meg 1/2 Watt on pins 2 and 4.
The resistor could not be in the chassis. There are not enough wires.
Warren has the right idea. The ohm meter won't lie.
It is possible that there was never a resistor installed in yours, a Q.C. escape.
If that were the case, though the 6G5 that came with the radio should still be good. It would have never glowed green to wear out the phosphor.
How did you get the tuning eye socket open?
Best Regards,
Bill G.
Clifton
:Hi Mitch,
: The resistor could not be in the chassis. There are not enough wires.
: Warren has the right idea. The ohm meter won't lie.
:
: It is possible that there was never a resistor installed in yours, a Q.C. escape.
: If that were the case, though the 6G5 that came with the radio should still be good. It would have never glowed green to wear out the phosphor.
: How did you get the tuning eye socket open?
:
:Best Regards,
:
:Bill G.
:
:
:Clifton
:
:
::Hi Mitch,
:: The resistor could not be in the chassis. There are not enough wires.
:: Warren has the right idea. The ohm meter won't lie.
::
:: It is possible that there was never a resistor installed in yours, a Q.C. escape.
:: If that were the case, though the 6G5 that came with the radio should still be good. It would have never glowed green to wear out the phosphor.
:: How did you get the tuning eye socket open?
::
::Best Regards,
::
::Bill G.
::
:
:
Hello everyone,
The information from all of you is correct. I just needed to follow your advice and see that what you said was how I needed to proceed on this. I do not want to burn out a $40.00 tube.
The Photo posted says it all. Seems that the blue and black wires are the filament.
No connection on #2 pin.
Yellow wire is on the #3 pin.
Red wire is on the #4 pin.
NC on the #5 pin.
The resistor seems to be between # 2 and #4 pins.
The resistor is open, no measurement with a meter.
Best approach to this repair is appreciated.
Why is there no wire connected to pin #2?
How do I get the old resistor out of the socket and replace with a 1/2 watt resistor.
All advice/comments welcome,
Thank you,
Mitchimg src=http://i1114.photobucket.com/albums/k537/wandzelm/PICT2893_zpsfe95acf7.jpg>
<
::
::Clifton
::
::
:::Hi Mitch,
::: The resistor could not be in the chassis. There are not enough wires.
::: Warren has the right idea. The ohm meter won't lie.
:::
::: It is possible that there was never a resistor installed in yours, a Q.C. escape.
::: If that were the case, though the 6G5 that came with the radio should still be good. It would have never glowed green to wear out the phosphor.
::: How did you get the tuning eye socket open?
:::
:::Best Regards,
:::
:::Bill G.
:::
::
::
:Hello everyone,
:
:The information from all of you is correct. I just needed to follow your advice and see that what you said was how I needed to proceed on this. I do not want to burn out a $40.00 tube.
:
:The Photo posted says it all. Seems that the blue and black wires are the filament.
:
:No connection on #2 pin.
:
:Yellow wire is on the #3 pin.
:
:Red wire is on the #4 pin.
:
:NC on the #5 pin.
:
:The resistor seems to be between # 2 and #4 pins.
:
:The resistor is open, no measurement with a meter.
:
:Best approach to this repair is appreciated.
:
:Why is there no wire connected to pin #2?
:
:How do I get the old resistor out of the socket and replace with a 1/2 watt resistor.
:
:All advice/comments welcome,
:
:Thank you,
:
:Mitchimg src=http://i1114.photobucket.com/albums/k537/wandzelm/PICT2893_zpsfe95acf7.jpg>
:
:
:
Ohm out between pins 5 and 6 or 1 and 5. You will find a connection there. In this application the cathode and one of the filaments is grounded, so they are taken to ground by a single wire.
From the looks of it you have a bit of a rewiring job. This is common with the connections to eye tubes.
All the Best,
Bill G.
See Schematic.
I would cut that old dog bone resistor in half with a small side cutter. Then you still have the end wires from the old resistor. Scrap and clean those wires, then solder a new 1 Meg 1/2 in place. That's what I do.
:
:Norm
:
:
::Hi Mitch,
:: You got really good luck! They will be sold out of 6G5 before the end of the year selling them at that price, especially now that you posted their web site here. I may go snatch one!
::
:: Count the wires coming from the socket. If you only have four, then the resistor was in there, but isn't any more. The resistor goes between pins 2 and 4 of the 6G5.
::
::Best Regards,
::
::Bill
::
:
:
Correct Norm,
I did receive a NOS 6U5 today, not a 6G5. That is OK with me.
A hand written note on the paid invoice from one of the company's owners said they did not think there was a 6G5 NOS on the planet. But, if I found one to give him a call.
Mitch