lite 2b from ao-35

[tonequest]

Howdy - Looking for some help on a ao-35 lite b - It all went together in the ao-35 chassis, board,iron with a 2x32uf electro can. It was interesting because I installed the board backwards from layout. It sounds good except when the tone control is used { works good when fully turned to the bass side } The noise is splatty like a loose string hitting the mag on a pickup with quick cut off sustain- The voltages are far from the ez81 targets - v1= 1 & 6 125 -- v2= 1&6 185 pin 2-46 pin 3 -56 and v3&4 = pin 3 -9.35 pin 7-322 pin 9 - 227v ---- 5y3 2&8 -321v pin4&6 299vac --heaters 3.14vac . Its pretty tight in the chassis but, the 60 &120hz is very low. thanks for taking the time - I will try to download some pics

[M Fowler]

Sounds like bad solder joint I would go over it and poke around with wood chop stick or nonmetallic stick.

I built one years ago and it was a fun project.

Mark

Lite IIB Hammod AO-35 conversion 001.JPG

[tonequest]

Thanks Mr. Fowler- Will check solder joints - I picked up a large roll of solder at a garage sale -tubes old radios etc. When I used the solder it did a dull bead ,so I switched back to tried and true. Might be the culprit -- thanks again - the pics are from an old iPod - will do better next time

[pompeiisneaks]

Thanks Mr. Fowler- Will check solder joints - I picked up a large roll of solder at a garage sale -tubes old radios etc. When I used the solder it did a dull bead ,so I switched back to tried and true. Might be the culprit -- thanks again - the pics are from an old iPod - will do better next time

It's possible the solder is fine but the flux is basically dead. You can still use that type of solder if you pre-flux the area to be soldered.

~Phil

[tonequest]

Alright - Reflowed all solder joints and its still a head scratcher - Amp sounds good when I adjust the volume to match the tone knob - kinda like on a radio searching for stations with the noise in-between - it also does the same thing with the tone knob { I find a good volume setting - then adjust the tone to get rid of noise - both pots work fine on minimum and maximum - Have tried different components around the 2 pots, other tubes - putting off a head shell till solved -- Any ideas would help immensely --- many thanks

[M Fowler]

I would look at the volume and tone pot wiring to make sure you have it right.

You wired it upside down to what I have so I drew it out to see if this is what you have.
I can't see all the wiring in the photos.

Mark

Marshall lite IIb volume and tone pot wiring.jpg

[tonequest]

Alright ! -- Thanks M Fowler - your a great citizen for lending a hand -- Got the thing much better. Removed the the shielded cable to the pots / turned the pots around so the tabs weren't so close to the OT / moved the shared ground off the 47k resistor to the chassis -- Cranked, this thing rocks -- so does Amp Garage

[M Fowler]

Great glad you got your amp up and running better. These amps are loud aren't they!

[tonequest]

Yep - Loud, proud - and a bit of attitude