:Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

:Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
:
::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

:Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
:
::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
::
:::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
:
:
:
::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
::
:::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
:::
::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

Does this equipment use a rectifier tube or does it use solid state diodes in the power supply or does any part of the power supply use solid state diodes?

Radiodoc
**********

:Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks
:
:
:: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
::
::
::
:::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
:::
::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
::::
:::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

Thanks for question. I do not know if it uses diodes as I do not know what to look for. It uses ECC 85, ECH81, EF89, EABC80 and EL84 tubes.

Del:
:
:Does this equipment use a rectifier tube or does it use solid state diodes in the power supply or does any part of the power supply use solid state diodes?
:
:Radiodoc
:**********
:
::Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks
::
::
::: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
:::
:::
:::
::::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
::::
:::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
:::::
::::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

There wasn't one of the tubes you listed that is a power supply rectifier tube. The radio must use a solid state rectifier(s). The rectifier(s) could possibly be in the form of a silicon diode(s) or possibly selenium. To get a look at what a solid state (silicon or germanium) diode looks like you may check out:

http://www.interq.or.jp/japan/se-inoue/e_diode.htm

To get an idea what a selenium rectifier looks you can look at:

http://www.theodoregray.com/PeriodicTable/Elements/034/

A selenium is pictured about half way down the page.

Radiodoc
***********

:
:
:
:Thanks for question. I do not know if it uses diodes as I do not know what to look for. It uses ECC 85, ECH81, EF89, EABC80 and EL84 tubes.
:
:Del:
::
::Does this equipment use a rectifier tube or does it use solid state diodes in the power supply or does any part of the power supply use solid state diodes?
::
::Radiodoc
::**********
::
:::Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks
:::
:::
:::: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
::::
::::
::::
:::::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
:::::
::::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
::::::
:::::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

:Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks
:
:
:: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
::
::
::
:::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
:::
::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
::::
:::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

:I may have figured out what the problem is with a photo of a similar radio on ebay. On the back cover is a hole which holds a slow blow fuse with a screw end which enters the a/c input metal housing inside the radio and connects to the red lead. The outer end of this fuse would rub against the metal surround of the a/c input. Inside the radio then is another fuse connecting the red to the input transformer. The line cord reads '7A;125V'. Perhaps I need to jury rig a surge fuse on the back cover and then use a larger than 2amp fuse inside. Any thoughts. The current 2 amp fuse inside pops right away. Thanks.
:
:
::Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks
::
::
::: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
:::
:::
:::
::::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
::::
:::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
:::::
::::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

This radio requires a 0,8 Amp fuse on 110/125 V mains - your 2 amp fuses are way too oversized.

It uses a selenium rectifier and it has three caps in the heater chain (2,2 nF, 5 nF and a 500 pF - probably two of them are paper caps.....)

So, i would check these, if the transformer is OK......

Kind regards, Walter Haring, Switzerland

: Del, if I understand correctly you are saying that a fuse holder in the back of the chassis was shorting out to the chassis? If thats so, before you change fuse value, correct the short and try the set again. The fact that you blow the fuse with no tubes in the set indicates a short in the power section of the set. You will have to correct the short in the fuse holder and if it still blows the fuse, disconnect primary of transformer and check to see if it is shorted. Also, if the set has line caps, change them they or one of them, may be shorted. Replace with new safety caps. PL
:
:
::I may have figured out what the problem is with a photo of a similar radio on ebay. On the back cover is a hole which holds a slow blow fuse with a screw end which enters the a/c input metal housing inside the radio and connects to the red lead. The outer end of this fuse would rub against the metal surround of the a/c input. Inside the radio then is another fuse connecting the red to the input transformer. The line cord reads '7A;125V'. Perhaps I need to jury rig a surge fuse on the back cover and then use a larger than 2amp fuse inside. Any thoughts. The current 2 amp fuse inside pops right away. Thanks.
::
::
:::Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks
:::
:::
:::: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
::::
::::
::::
:::::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
:::::
::::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
::::::
:::::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

:Hi all
:
:This radio requires a 0,8 Amp fuse on 110/125 V mains - your 2 amp fuses are way too oversized.
:
:It uses a selenium rectifier and it has three caps in the heater chain (2,2 nF, 5 nF and a 500 pF - probably two of them are paper caps.....)
:
:So, i would check these, if the transformer is OK......
:
:Kind regards, Walter Haring, Switzerland
:
:
:: Del, if I understand correctly you are saying that a fuse holder in the back of the chassis was shorting out to the chassis? If thats so, before you change fuse value, correct the short and try the set again. The fact that you blow the fuse with no tubes in the set indicates a short in the power section of the set. You will have to correct the short in the fuse holder and if it still blows the fuse, disconnect primary of transformer and check to see if it is shorted. Also, if the set has line caps, change them they or one of them, may be shorted. Replace with new safety caps. PL
::
::
:::I may have figured out what the problem is with a photo of a similar radio on ebay. On the back cover is a hole which holds a slow blow fuse with a screw end which enters the a/c input metal housing inside the radio and connects to the red lead. The outer end of this fuse would rub against the metal surround of the a/c input. Inside the radio then is another fuse connecting the red to the input transformer. The line cord reads '7A;125V'. Perhaps I need to jury rig a surge fuse on the back cover and then use a larger than 2amp fuse inside. Any thoughts. The current 2 amp fuse inside pops right away. Thanks.
:::
:::
::::Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks
::::
::::
::::: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL
:::::
:::::
:::::
::::::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem????
::::::
:::::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck.
:::::::
::::::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks.

I am at a hopeless disadvantage in not having a schematic for referencing, but I can refer to the 2628 Granada or 2623 Sultan, which might be a 'skosh newer...? and even they are using a 3AG eight / tenths of an amp at 250 volts slow blow fuse in that unit. So if you are taking out a 2 amp...you've definitely got something wrong in River City. No trouble in clarifing the Euro values....just slip the decimal point over three places to the left and your 2.2 and 5 "ninny" farads magically becomes .0022 ufd and its companion is .005 ufd and you certainly should have no problem with the 500 pf as being the old designated 500 micro-micro farads or .0005 ufd...current terminology...but the picofarads is the current preferred designator. These werre used in the tail end of the RF circuitry at the ratio detector,2nd FM IF amp as well as up in the front at the FM converter on bypassing its fil supply lines. As far as their failure down into a short, they would be the very last items on my check list of candidates. My referenced unit also shows a Full Wave Bridge selenium rectifier used also....with the option of also utilizing 4 common silicon diodes configured to a FWB configuration. Can't help on the 18/0.5 diodes, without a schema confirmation and only assume to be an 18V rating and .5 amp current rating, but the unit I am referring to has NO series of diodes even being used in its design. Any chance that you can get me a schema ..or thumbnail thereof...to reference. Getting back to the "fussee blowee-bloweee" aspect..... I see the primary of the power transformer and its ISOLATED high voltage secondary as well as its ISOLATED filament winding. If you were getting contact to the chassis thru the primary winding I could only see the chassis being hot...and only a 50/50 chance at that with the way the AC plug is inserted into the AC socket....if the loop to ground of the chassis was completed by the chassis being at ground potential. Be that by virtue of the chassis being upon a metal bench that is grounded or the other possibility of the unit being connected to a cable / wire that is grounded...for a connected outdoor antenna or a CABLE coaxial connector with its grounded outer shield, that is always carrying a ground . The other possibility being that the secondary filament or high voltage winding is also broken down insulatively and connecting to the primary or ground also , where a short could occur. Soooooo, if this were my situation, I would isolate and shed all loads. Starting with..and I certainly hope the color codings are concurrent... a clipping ...(near to a junction where it can be resoldered) of the red wire on the primary and the black yel will automatically be isolated if the switch is in its off position. Then you measure resistance from both ends of the primary winding to the chassis ground and then see if there is any low resistance.....if it is isolated......then measure likewise, from the primary winding, but over to the HV secondary and then to the filament winding for low resistance. I am going to break here and wait for a comeback on your findings. Thumbnail: 73's de Edd 7/12/2007 1:34:41 PMDel in MN(51998:51995) Thanks to all. Got the correct fuses and it seems to be fine. Simply, thanks to all. ::What are USA values for 2.2nf, 5nf and 500pf. Thanks to Walter. On the scehmatic I see the 500 as C747 but I do not see the others in the heater chain. What are D704, D705 and D702? They are all 18/0.5. Are these diodes? ::Thanks very much. :: :::Hi all ::: :::This radio requires a 0,8 Amp fuse on 110/125 V mains - your 2 amp fuses are way too oversized. ::: :::It uses a selenium rectifier and it has three caps in the heater chain (2,2 nF, 5 nF and a 500 pF - probably two of them are paper caps.....) ::: :::So, i would check these, if the transformer is OK...... ::: :::Kind regards, Walter Haring, Switzerland ::: ::: :::: Del, if I understand correctly you are saying that a fuse holder in the back of the chassis was shorting out to the chassis? If thats so, before you change fuse value, correct the short and try the set again. The fact that you blow the fuse with no tubes in the set indicates a short in the power section of the set. You will have to correct the short in the fuse holder and if it still blows the fuse, disconnect primary of transformer and check to see if it is shorted. Also, if the set has line caps, change them they or one of them, may be shorted. Replace with new safety caps. PL :::: :::: :::::I may have figured out what the problem is with a photo of a similar radio on ebay. On the back cover is a hole which holds a slow blow fuse with a screw end which enters the a/c input metal housing inside the radio and connects to the red lead. The outer end of this fuse would rub against the metal surround of the a/c input. Inside the radio then is another fuse connecting the red to the input transformer. The line cord reads '7A;125V'. Perhaps I need to jury rig a surge fuse on the back cover and then use a larger than 2amp fuse inside. Any thoughts. The current 2 amp fuse inside pops right away. Thanks. ::::: ::::: ::::::Planigan: Thanks. I pulled all of the tubes and turned set on. 2 amp fuse popped right away. I check 2 filter caps for polarity and negative goes to chassis. Any more help out there? Thanks :::::: :::::: ::::::: Del, try pulling all tubes and turn set on, if ok turn off and put in rectifier tube and turn on, if ok your power circuit and the caps are OK you have a short someplace further down the line. If you blow fuse without tubes your transformer may be shorted or a mis-wire. If the fuse blows with just rectifier, your problem could be secondary shorted, caps in with wrong polarity or wiring, short somewhere in B+ curcuit. PL ::::::: ::::::: ::::::: ::::::::Disconnected negative side of caps and 2 amp slow blow fuse popped right away. Any more suggestions. The schematic shows no chassis ground from the input and thru the transformer. On this set one side of the 110 input shows continuity with chassis. That must be the problem???? :::::::: :::::::::Easy check, Unhook both caps and try it again. Still blows, short somewhere else. Doesn't blow, something wrong with caps or installation. Good luck. ::::::::: ::::::::::Trying to figure out why the 800mA fuse pops right away. Have put in the 2 50mf, 350V caps. Any suggestions and thanks. : : : : : : :I am at a hopeless disadvantage in not having a schematic for referencing, but I can refer to the 2628 Granada or 2623 Sultan, which might be a 'skosh newer...? and even they are using a 3AG eight / tenths of an amp at 250 volts slow blow fuse in that unit. : :So if you are taking out a 2 amp...you've definitely got something wrong in River City. : : :No trouble in clarifing the Euro values....just slip the decimal point over three places to the left and your 2.2 and 5 "ninny" farads magically becomes .0022 ufd and its companion is .005 ufd and you certainly should have no problem with the 500 pf as being the old designated 500 micro-micro farads or .0005 ufd...current terminology...but the picofarads is the current preferred designator. : :These werre used in the tail end of the RF circuitry at the ratio detector,2nd FM IF amp as well as up in the front at the FM converter on bypassing its fil supply lines. As far as their failure down into a short, they would be the very last items on my check list of candidates. : : : :My referenced unit also shows a Full Wave Bridge selenium rectifier used also....with the option of also utilizing 4 common silicon diodes configured to a FWB configuration. : : : :Can't help on the 18/0.5 diodes, without a schema confirmation and only assume to be an 18V rating and .5 amp current rating, but the unit I am referring to has NO series of diodes even being used in its design. : :Any chance that you can get me a schema ..or thumbnail thereof...to reference. : : : :Getting back to the "fussee blowee-bloweee" aspect..... I see the primary of the power transformer and its ISOLATED high voltage secondary as well as its ISOLATED filament winding. : : : :If you were getting contact to the chassis thru the primary winding I could only see the chassis being hot...and only a 50/50 chance at that with the way the AC plug is inserted into the AC socket....if the loop to ground of the chassis was completed by the chassis being at ground potential. Be that by virtue of the chassis being upon a metal bench that is grounded or the other possibility of the unit being connected to a cable / wire that is grounded...for a connected outdoor antenna or a CABLE coaxial connector with its grounded outer shield, that is always carrying a ground . : :The other possibility being that the secondary filament or high voltage winding is also broken down insulatively and connecting to the primary or ground also , where a short could occur. : : : :Soooooo, if this were my situation, I would isolate and shed all loads. Starting with..and I certainly hope the color codings are concurrent... a clipping ...(near to a junction where it can be resoldered) of the red wire on the primary and the black yel will automatically be isolated if the switch is in its off position. Then you measure resistance from both ends of the primary winding to the chassis ground and then see if there is any low resistance.....if it is isolated......then measure likewise, from the primary winding, but over to the HV secondary and then to the filament winding for low resistance. : :I am going to break here and wait for a comeback on your findings. : : : :Thumbnail: : : : : :73's de Edd : : : : : : : : © 1989-2025, Nostalgia Air