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C-70 Repair - Pre out jacks are bad -

J

JoeMt

New Member
Hi It appears my Pre out jacks are bad. It's not a broken solder joint on the board.

1. Does anyone have this part?

2. Are their excellent techs here who provide restoration on the M/C/T - 70 's??? What does it entail and idea of cost. Yes I know Legendary is an option.
 
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JoeMt said:
Hi It appears my Pre out jacks are bad. It's not a broken solder joint on the board.

1. Does anyone have this part?

2. Are their excellent techs here who provide restoration on the M/C/T - 70 's??? What does it entail and idea of cost. Yes I know Legendary is an option.
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"Legendary?"

Oh please.
 
The jack(s) (all 4) itself is loose in the assembly. Solder joints look fine. If I hold it (with cable plugged in) I have sound. I let go it quits. I'm not sure what the other guy did I got it that way. IF I can't find the part I was going to swapped the "direct Phono" assembly to the Pre amp out.....Those are very tight.

I'm I missing something? thoughts?
 
Ok I misread a couple things. I won't ever use "phono direct". And down the road if I find a parts unit or a kind soul who has one to sell me. I can replace it later...for what ever reason. I just want to listen to music in my home.
 
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Well I started dropping a channel again.....at one time the transistors were replaced on the large heat syncs. I re soldered those and things got better but not perfect I went in again and found some more bad solder joints.....better yet.. I also used the deoxit D5 on the banana ports seems to have helped. Worked all day yesterday. I will keep at it. Question on the deoxit. Do you spray that into the switches on the C-70 preamp? over spray an issue?
 
C-70 preamps have 7 small yellow HB2E-DC24V relays. That do often go intermittent. Next time it acts up on you. Give these little rascals a tap or two and see if it cuts in and out on you.
 
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There is also two TO-220 transistors close to the two fuses. TR537 and 538. These are the 17 volt regulated power supply pass transistors. If you haven't already. Reflow there solder connections.
I have a C-70 here that these two were definitely loose. If they act up it will mess up both channels.
 
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JoeMt said:
Question on the deoxit. Do you spray that into the switches on the C-70 preamp? over spray an issue?
Click to expand...
All the switches on the C-70 are those darn slide switches that are damn near impossible to get clean without removing them and disassembling them.
 
You still need parts? If so can go back in garbage bin to scrape parts for you. Just put it there earlier after they got collected.
 
Houas07tc said:
You still need parts? If so can go back in garbage bin to scrape parts for you. Just put it there earlier after they got collected.
Click to expand...
They would probably be just as dirty as the switches he has presently.
 
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