I'm trying to repair an old radio from Delco, Model 985264. Its a transistor car radio, made for Chevrolet.The problem is in the LF part, the radio works bud the amplefier does not. Can somebody help me on the schematic drawing of this radio, or a part of the schematic from the LF part?
Thank you in advance,
73, PE1OPC,
Leo Snoeren from holland.
Are you trying to locate a replacement for one of the transistors, or just a circuit to circuit trace?
Just mentioning a common troubleshooting error on those radios made by Delco for the GM products have to have 2 wires to the speaker, one side cannot be tied to chassis ground, or the audio is inoperative. Did the large capacitor get checked or replaced? This has been a fairly common source of trouble on those earlier radios.
Another 2 things for a quick check are the resistor to the emitter of the power transistor as it may be burned out (check the condition of the transistor if it is), and solder joints/solder tracks. One may have broken loose, or may have been a cold solder joint from the begining.
:Hello,
:
:I'm trying to repair an old radio from Delco, Model 985264. Its a transistor car radio, made for Chevrolet.The problem is in the LF part, the radio works bud the amplefier does not. Can somebody help me on the schematic drawing of this radio, or a part of the schematic from the LF part?
:
:Thank you in advance,
:
:73, PE1OPC,
:Leo Snoeren from holland.
The radio has several problems, the main problem is, that there was some one befor me who has tried fixing the radio. He fixed the wires from the final AF amp. by loosning them (there was nothing wrong with them) and now i don't know witch wire where to connect. He also fixed an IF transformer by distroying the coils, and finaly he cut some wires on several places. Most of these things i've repairt and the radio is working again, but just until the volume adjustment. After this point nothing seems to work. I've also found some broken traces on the board and fixed them. The final AF transistor is broken (shortcut E>C) this is a Delco DS501. Replacemant is not the problem, i can replace it with a european germanium transistor, but i need to know if it's a PNP or NPN type. Strangely voltages i measure: on the AF potentiometer, almost everything is between 10 en 12 Volts?
The book you mensiond, is not availeble in the Netherlands, perhaps someone can send me a copy or someting? My e-mail account is leosnoeren@rrd.demon.nl
:Hi,
:At the moment those are not online that I am aware of, but if you can get ahold of either a Sam's Automotive Radio volume "AR-17", or if you know someone who has the folder sets, it will also be in folder sleeve set 605 folder number 4.
:
:Are you trying to locate a replacement for one of the transistors, or just a circuit to circuit trace?
:
:Just mentioning a common troubleshooting error on those radios made by Delco for the GM products have to have 2 wires to the speaker, one side cannot be tied to chassis ground, or the audio is inoperative. Did the large capacitor get checked or replaced? This has been a fairly common source of trouble on those earlier radios.
:
:Another 2 things for a quick check are the resistor to the emitter of the power transistor as it may be burned out (check the condition of the transistor if it is), and solder joints/solder tracks. One may have broken loose, or may have been a cold solder joint from the begining.
:
:
:
::Hello,
::
::I'm trying to repair an old radio from Delco, Model 985264. Its a transistor car radio, made for Chevrolet.The problem is in the LF part, the radio works bud the amplefier does not. Can somebody help me on the schematic drawing of this radio, or a part of the schematic from the LF part?
::
::Thank you in advance,
::
::73, PE1OPC,
::Leo Snoeren from holland.
Leo,
The Delco DS501 transistor is a PNP germanium type in a TO-36 case. An NTE/ECG 105 is a replacement.
radiodoc
I can send a copy of the Delco service sheet by Airmail Letter-Post. Email me your mailing address.
m.grazier"AT"verizon.net
Meade
::Hi,
::
::The radio has several problems, the main problem is, that there was some one befor me who has tried fixing the radio. He fixed the wires from the final AF amp. by loosning them (there was nothing wrong with them) and now i don't know witch wire where to connect. He also fixed an IF transformer by distroying the coils, and finaly he cut some wires on several places. Most of these things i've repairt and the radio is working again, but just until the volume adjustment. After this point nothing seems to work. I've also found some broken traces on the board and fixed them. The final AF transistor is broken (shortcut E>C) this is a Delco DS501. Replacemant is not the problem, i can replace it with a european germanium transistor, but i need to know if it's a PNP or NPN type. Strangely voltages i measure: on the AF potentiometer, almost everything is between 10 en 12 Volts?
::
::The book you mensiond, is not availeble in the Netherlands, perhaps someone can send me a copy or someting? My e-mail account is leosnoeren@rrd.demon.nl
::
:::Hi,
:::At the moment those are not online that I am aware of, but if you can get ahold of either a Sam's Automotive Radio volume "AR-17", or if you know someone who has the folder sets, it will also be in folder sleeve set 605 folder number 4.
:::
:::Are you trying to locate a replacement for one of the transistors, or just a circuit to circuit trace?
:::
:::Just mentioning a common troubleshooting error on those radios made by Delco for the GM products have to have 2 wires to the speaker, one side cannot be tied to chassis ground, or the audio is inoperative. Did the large capacitor get checked or replaced? This has been a fairly common source of trouble on those earlier radios.
:::
:::Another 2 things for a quick check are the resistor to the emitter of the power transistor as it may be burned out (check the condition of the transistor if it is), and solder joints/solder tracks. One may have broken loose, or may have been a cold solder joint from the begining.
:::
:::
:::
::::Hello,
::::
::::I'm trying to repair an old radio from Delco, Model 985264. Its a transistor car radio, made for Chevrolet.The problem is in the LF part, the radio works bud the amplefier does not. Can somebody help me on the schematic drawing of this radio, or a part of the schematic from the LF part?
::::
::::Thank you in advance,
::::
::::73, PE1OPC,
::::Leo Snoeren from holland.
:
:Leo,
:
:The Delco DS501 transistor is a PNP germanium type in a TO-36 case. An NTE/ECG 105 is a replacement.
:
:radiodoc
:
I wanna thank everybody for the help and advises given to me. Especially Bill, for sending me the cicuit diagrams. This will make it posseble to repair the radio. I also wanna thank Meade, for the equivalent type for the DS501 transistor.
I'll let you know when the radio is working again!
If i can do something in return: i have a large collection of circuit diagrams from (European) Philips tube radios, dont hazertate to ask me!
Leo Snoeren
Sorry,
Meade must be "Radiodoc"
Leo
The radio is working again, but there is a problem: the transtormer between the pré and final AF amplefier is shortcircuit. I've put an other transformer in the radio, but i's not the correct type. I'm trying to rewind the defective transformer, only the primairy site has 2300 windings, with gonna cost me some time!
Leo