Okay...I must confess. I screwed up and accidentally crossed circuits and, consequently, lost all power and all signs of life in my Firestone radio. When something like that happens, what actually "blows"? I have tested the tubes and they're good. Before I blew out the radio, I replaced a capacitors.
Can someone tell stear me in the right direction for troubleshooting and for bringing my beloved Firestone back to life?
What a blunder I committed!!
Sincerely,
Kory

Kory,

With the radio unpluged, measure the resistance across the on/off switch to make sure it is still good. Should measure zero Ohms. Also measure resistance of each side of the line cord from plug to connection under chassis.

Radiodoc
**********

:Okay...I must confess. I screwed up and accidentally crossed circuits and, consequently, lost all power and all signs of life in my Firestone radio. When something like that happens, what actually "blows"? I have tested the tubes and they're good. Before I blew out the radio, I replaced a capacitors.
:Can someone tell stear me in the right direction for troubleshooting and for bringing my beloved Firestone back to life?
:What a blunder I committed!!
:Sincerely,
:Kory

:Kory,
:
:With the radio unpluged, measure the resistance across the on/off switch to make sure it is still good. Should measure zero Ohms. Also measure resistance of each side of the line cord from plug to connection under chassis.
:
:Radiodoc
:**********

Kory:
Sometimes, when things look darkest, they are the easiest to fix. Assuming the tube filaments are not lit, after doing as Radiodox says, then check from one pin of the power cord to the first filament, second filament, and so on until you find out where the open is. Might be a fifteen minute job to locate.
Lewis
:
:
::Okay...I must confess. I screwed up and accidentally crossed circuits and, consequently, lost all power and all signs of life in my Firestone radio. When something like that happens, what actually "blows"? I have tested the tubes and they're good. Before I blew out the radio, I replaced a capacitors.
::Can someone tell stear me in the right direction for troubleshooting and for bringing my beloved Firestone back to life?
::What a blunder I committed!!
::Sincerely,
::Kory

::Kory,
::
::With the radio unpluged, measure the resistance across the on/off switch to make sure it is still good. Should measure zero Ohms. Also measure resistance of each side of the line cord from plug to connection under chassis.
::
::Radiodoc
::**********
:
:
:Kory:
:Sometimes, when things look darkest, they are the easiest to fix. Assuming the tube filaments are not lit, after doing as Radiodox says, then check from one pin of the power cord to the first filament, second filament, and so on until you find out where the open is. Might be a fifteen minute job to locate.
:Lewis
::
::
:::Okay...I must confess. I screwed up and accidentally crossed circuits and, consequently, lost all power and all signs of life in my Firestone radio. When something like that happens, what actually "blows"? I have tested the tubes and they're good. Before I blew out the radio, I replaced a capacitors.
:::Can someone tell stear me in the right direction for troubleshooting and for bringing my beloved Firestone back to life?
:::What a blunder I committed!!
:::Sincerely,
:::Kory
Hi Kory,
My experience with this kind of thing is that the 35Z5GT is the tube that blows. The tube may check good if the filament between pins 2 and 3 is open because the filament between 3 and 7 will stay good.

Best Regards,

Bill Grimm

Gentlemen!
Thanks for the replies. As it turns out, the 35Z5GT tube was bad (so much for trusting the tube tester!).
So......now I'm back where I started BEFORE I blew the 35Z5 tube. That is, the radio turns on, I hear sound (static and a slight hum), but I receive no signal. There is no crackle when I hook up an antenna to the set nor does the radio crack if I probe around the tuner slides. It's as if it is paralyzed in terms of reception. Any ideas to this problem?
Thanks,again, for your previous help!
Learning as I go....
Kory

:::Kory,
:::
:::With the radio unpluged, measure the resistance across the on/off switch to make sure it is still good. Should measure zero Ohms. Also measure resistance of each side of the line cord from plug to connection under chassis.
:::
:::Radiodoc
:::**********
::
::
::Kory:
::Sometimes, when things look darkest, they are the easiest to fix. Assuming the tube filaments are not lit, after doing as Radiodox says, then check from one pin of the power cord to the first filament, second filament, and so on until you find out where the open is. Might be a fifteen minute job to locate.
::Lewis
:::
:::
::::Okay...I must confess. I screwed up and accidentally crossed circuits and, consequently, lost all power and all signs of life in my Firestone radio. When something like that happens, what actually "blows"? I have tested the tubes and they're good. Before I blew out the radio, I replaced a capacitors.
::::Can someone tell stear me in the right direction for troubleshooting and for bringing my beloved Firestone back to life?
::::What a blunder I committed!!
::::Sincerely,
::::Kory
:Hi Kory,
: My experience with this kind of thing is that the 35Z5GT is the tube that blows. The tube may check good if the filament between pins 2 and 3 is open because the filament between 3 and 7 will stay good.
:
:Best Regards,
:
:Bill Grimm

.........Probably what you did when you shorted out the B supply is you burned out the lamp tap in the 35Z5, which is both in series with the filaments and the B supply. The reason why you won't catch this on a tube tester is because most tube testers are not capable of isolating the lamp tap whilst making tests. Take your ohm meter and measure across pins 2 and 3. If open, replace the tube.

You can find 35Z5s on eBay, if you can't get them from other sources (since someone said that two major ones are out of tubes). You can also use a 45Z5, which is available at many places. Another option, if your 35Z5 otherwise tests good, would be to connect two 6.8 or 7.0 volt zener diodes back-to-back (in series, with either the cathodes or the anodes facing eachother). Connect them across pins 2 and 3 of the rectifier. That will allow you to keep using your otherwise fine rectifier. Be sure to replace the pilot lamp. Do not operate the radio without its #47 pilot lamp (available at Radio Shack and most hardware stores, or any other similar sized 6.3 volt .15 ampere bulb). If you decide to replace the 35Z5 in the future, you can leave the zener diodes in place. Everything will work just fine. You will notice, however, that the pilot lamp won't glow really brightly when the radio is first turned on. Instead, with your current 35Z5, it'll keep a fairly steady glow, and with a new 35Z5 (with a good lamp tap), it'll glow regular brilliance, or dimmer while the tubes are warming up, but it'll never get to the super brightness that it used to get to when the set was turned on cold.

If you short your B supply again, you will blow the zeners. If you want, put a .25 or .5 ampere slow blow fuse in series with pin 8 and the radio's B circuit. That'll somewhat protect future tubes and zener diodes, etc. Try the .25 ampere fuse first. If it blows too easily, move up. You can find .25 ampere fuses at Radio Shack.

T.

Thomas,
You certainly know your stuff. Unfortunately (or fortunately), I'm a U.S. History teacher and not an electrician. I must admit, the extent of my radio restoration know-how is pretty much limited to recapping and other very basic functions (though I love the challenge of learning something new). Presently, I don't even know what a zener diode is, but I will before the night is over!
T, thanks for the challenge! I've got plenty to look up!
Kory

:.........Probably what you did when you shorted out the B supply is you burned out the lamp tap in the 35Z5, which is both in series with the filaments and the B supply. The reason why you won't catch this on a tube tester is because most tube testers are not capable of isolating the lamp tap whilst making tests. Take your ohm meter and measure across pins 2 and 3. If open, replace the tube.
:
:You can find 35Z5s on eBay, if you can't get them from other sources (since someone said that two major ones are out of tubes). You can also use a 45Z5, which is available at many places. Another option, if your 35Z5 otherwise tests good, would be to connect two 6.8 or 7.0 volt zener diodes back-to-back (in series, with either the cathodes or the anodes facing eachother). Connect them across pins 2 and 3 of the rectifier. That will allow you to keep using your otherwise fine rectifier. Be sure to replace the pilot lamp. Do not operate the radio without its #47 pilot lamp (available at Radio Shack and most hardware stores, or any other similar sized 6.3 volt .15 ampere bulb). If you decide to replace the 35Z5 in the future, you can leave the zener diodes in place. Everything will work just fine. You will notice, however, that the pilot lamp won't glow really brightly when the radio is first turned on. Instead, with your current 35Z5, it'll keep a fairly steady glow, and with a new 35Z5 (with a good lamp tap), it'll glow regular brilliance, or dimmer while the tubes are warming up, but it'll never get to the super brightness that it used to get to when the set was turned on cold.
:
:If you short your B supply again, you will blow the zeners. If you want, put a .25 or .5 ampere slow blow fuse in series with pin 8 and the radio's B circuit. That'll somewhat protect future tubes and zener diodes, etc. Try the .25 ampere fuse first. If it blows too easily, move up. You can find .25 ampere fuses at Radio Shack.
:
:
:
:T.

Research it on the internet. I'm not too interested in modern electronics, but zener diodes can certainly do some wonderful things.

I purchased a 100 pack of 6.8 volt zeners on eBay. I'm sure that there are other inexpensive sources, too.

T.

:Research it on the internet. I'm not too interested in modern electronics, but zener diodes can certainly do some wonderful things.
:
:I purchased a 100 pack of 6.8 volt zeners on eBay. I'm sure that there are other inexpensive sources, too.
:
:T.
A Zener diode (capatilized because it is named after Carl Zener, who figured it out) is a diode that is calibrated to start conduction at a certain reverse Voltage. To learn more, check out this site:

http://sound.westhost.com/appnotes/an008.htm

You can get more complicated later.
Lewis

Thanks, Gents!
I'm always learning something new about radios...and I've got a long, long way to go!

::Research it on the internet. I'm not too interested in modern electronics, but zener diodes can certainly do some wonderful things.
::
::I purchased a 100 pack of 6.8 volt zeners on eBay. I'm sure that there are other inexpensive sources, too.
::
::T.
:A Zener diode (capatilized because it is named after Carl Zener, who figured it out) is a diode that is calibrated to start conduction at a certain reverse Voltage. To learn more, check out this site:
:
:http://sound.westhost.com/appnotes/an008.htm
:
:You can get more complicated later.
:Lewis
:
:
:
:
:

Kory, don't feel bad, we all have and will continue to make mistake, just the other day at work I hooked up a new printed wiring board to a power supply incorrectly - reversed the plus and neg leads. End results was no damage, just additional time trying to figure out what I did (I have made these connection many times before, as well as help other troubleshoot their setups).

Good luck and hang in there.

David S

:Okay...I must confess. I screwed up and accidentally crossed circuits and, consequently, lost all power and all signs of life in my Firestone radio. When something like that happens, what actually "blows"? I have tested the tubes and they're good. Before I blew out the radio, I replaced a capacitors.
:Can someone tell stear me in the right direction for troubleshooting and for bringing my beloved Firestone back to life?
:What a blunder I committed!!
:Sincerely,
:Kory

:Kory, don't feel bad, we all have and will continue to make mistake, just the other day at work I hooked up a new printed wiring board to a power supply incorrectly - reversed the plus and neg leads. End results was no damage, just additional time trying to figure out what I did (I have made these connection many times before, as well as help other troubleshoot their setups).

Kory:
I once caught an airliner on fire. Somebody else wired it wrong, but I didn't catch the mistake until I flipped the "External Power On" switch, and all hell broke loose.
Lewis

:
:Good luck and hang in there.
:
:David S
:
::Okay...I must confess. I screwed up and accidentally crossed circuits and, consequently, lost all power and all signs of life in my Firestone radio. When something like that happens, what actually "blows"? I have tested the tubes and they're good. Before I blew out the radio, I replaced a capacitors.
::Can someone tell stear me in the right direction for troubleshooting and for bringing my beloved Firestone back to life?
::What a blunder I committed!!
::Sincerely,
::Kory