excabincrew
Active Member
I think the socket is loosen during shipping. Can it be tighten from the top without opening the amp?
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Mcintosh mc30
- Thread starter excabincrew
- Start date
excabincrew
Active Member
Please let me know, thanks
excabincrew
Active Member
Thanks again Pio
excabincrew
Active Member
Do I need to discharge first or is it safe just to tightening the socket using small screw driver?
Never use a screwdriver
What did you determine here?
excabincrew
Active Member
Well as of today, nothing is done. I took out the tube rectifier and saw one of the pin slightly bent. While doing that I took a look at the socket and kinda puzzle, not really sure if I want to work on the socket first after seeing the pin. I am now going to buy nos rca in ebay. Since I am newbie and have brown thumb, I choose to to replace the tube first. If it s not because of discharge I would probably buy yhe dental pick and start adjusting the socket. Thanks for asking.
excabincrew
Active Member
excabincrew
Active Member
The socket bit in the hole left of the key way looks stretched, that is position 8, one of the filament pins. That needs adjusting.
Pins are numbered clockwise from the keyway as seen from the bottom of the tube socket.
Pins used for the 5U4 are 2, 4, 6, 8.
2 and 8 are filament, 4 and 6 are anode plates. Those four are the ones to adjust if needed.
https://goo.gl/images/jtqKuF
Pins are numbered clockwise from the keyway as seen from the bottom of the tube socket.
Pins used for the 5U4 are 2, 4, 6, 8.
2 and 8 are filament, 4 and 6 are anode plates. Those four are the ones to adjust if needed.
https://goo.gl/images/jtqKuF
excabincrew
Active Member
Oh wow , many thanks Pio
excabincrew
Active Member
I thought my tube has 5 pins?
It has five, four used and one (pin 1) is blank.
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excabincrew
Active Member
I see, I am I not home now but remembered my number 2 is the one that slightly bent and a little corroded. My tube was born 1959, has the rca writing on it instead at the base
Bill Ferris
Lunatic Member
FWIW folks, Ref: tube socket re-tensioning ..
Iv`e had excellent results for many decades using the large diaper safety pins straightened out while repairing many guitar amps.
It was part of my standard routine for all vintage amps before hosing out all tube sockets with contact cleaner ...
This procedure was most especially important for combo tube amps, as the tubes hang upside down, and not all models had tube retainer clips.
I had SS dental picks too, but they tended to get buggered up using them in that application, so I went the inexpensive big diaper safety pin method back in the late eighties, and haven`t looked back..
I also found dental drill bits helpful for "mildly" scraping out the large tube pin sockets when corrosion was present, as these amps were played in FL., and salt air/humidity were ever present .
Anyway.
Just a thought/suggestion folks.
Take care.
Kind regards, OKB
Iv`e had excellent results for many decades using the large diaper safety pins straightened out while repairing many guitar amps.
It was part of my standard routine for all vintage amps before hosing out all tube sockets with contact cleaner ...
This procedure was most especially important for combo tube amps, as the tubes hang upside down, and not all models had tube retainer clips.
I had SS dental picks too, but they tended to get buggered up using them in that application, so I went the inexpensive big diaper safety pin method back in the late eighties, and haven`t looked back..
I also found dental drill bits helpful for "mildly" scraping out the large tube pin sockets when corrosion was present, as these amps were played in FL., and salt air/humidity were ever present .
Anyway.
Just a thought/suggestion folks.
Take care.
Kind regards, OKB
Bill Ferris
Lunatic Member
Well Sir, outside of simply straightening out the large diaper safety pin, the tube socket re-tensioning procedure seems well explained in post 24, and your youTube video in post # 43, that I went back and watched, before responding to your suggestion above..
The MC 30 owner needs to be aware of needing the amp unplugged and PS caps fully discharged, before poking any conductive implement into the tube socket female connections, or practice the one hand safety rule, or leave the amp off for a month !!
Are you wishing me to be redundant here, as I`m typing with one finger ??
Thanks.
Regards, OKB
