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Hello again....I am need of your combined wisdom again folks...I have a little 610 shouldered tombstone I just recapped. I've done a ton of the block caps so I re-stuffed them correctly. I replaced all of the out of range resistor I could find. I used a 2 watt 20-ohm to replace the out of range 10,000 ohm dog bone resistor in the electrolytic section. Per the schematic I hooked the negative ends of the two replacement electrolytic caps one to the 235 ohm tap and the other to the ground end tap of the part #57 two tap resistor. Parts list lists it as 33-3037. I hooked the negative end of the 16 mfd cap to ground per schematic. The set comes on, it will not receive stations. No tubes overheat. There is a popping noise when turn the tone control from one setting to another. No noise is heard when I put my finger on the grid cap of the 6A7, 78 or 75. Any suggestions? I am stuck. Thanks for any help you can offer!
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Hello. Did you check the Antenna & OSC. transformer coils for continuity? You also might check tube voltages to see what readings you get.
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(09-07-2015, 08:39 PM)dfields69 Wrote: Hello again....I am need of your combined wisdom again folks...I have a little 610 shouldered tombstone I just recapped. I've done a ton of the block caps so I re-stuffed them correctly. I replaced all of the out of range resistor I could find. I used a 2 watt 20-ohm to replace the out of range 10,000 ohm dog bone resistor in the electrolytic section. Per the schematic I hooked the negative ends of the two replacement electrolytic caps one to the 235 ohm tap and the other to the ground end tap of the part #57 two tap resistor. Parts list lists it as 33-3037. I hooked the negative end of the 16 mfd cap to ground per schematic. The set comes on, it will not receive stations. No tubes overheat. There is a popping noise when turn the tone control from one setting to another. No noise is heard when I put my finger on the grid cap of the 6A7, 78 or 75. Any suggestions? I am stuck. Thanks for any help you can offer!
Have you checked the IF cans? Verify that their resistance value is close to the schematic. Check all components and wiring in the signal path, starting backwards from the audio output stage.
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If you get no hum when you touch the grid cap of the 75, there is a problem in the output. Work from the 75 toward the output.
Steve
M R Radios C M Tubes
(This post was last modified: 09-07-2015, 11:29 PM by
Steve Davis.)
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Thank you for every bit of this! Very useful...I'm working on it again over this weekend. Will post with results. This is the best site I've been on and the most helpful!
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As Steve indicated you need to get some hum on the output. Don't worry about the front end of the radio at this time. Do some voltage measurements. Check the output transformer and speaker. Get some hum when touching the center tap of the volume control before worrying about other areas.
Jerry
A friend in need is a pest! Bill Slee ca 1970.
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You always want to get the output working first. A working output is very useful for troubleshooting the rest of the radio.
Steve
M R Radios C M Tubes
