Seeburg MRA5-L6 ground buss

Q&A about all types of jukeboxes: Wurlitzer, Seeburg, Rock-Ola, AMI, and more.



Topic author
Steve_B
Regular Member
Posts: 46
Joined: Sat Jan 02, 2016 7:23 pm
Location: Paramus, New Jersey, USA

Seeburg MRA5-L6 ground buss

by Steve_B » Sun May 22, 2016 3:25 pm

I have read elsewhere that connecting filter caps and the transformer ground to the same ground buss can result in increased hum due to an effect on the pre-amp stage. Should the transformer (T1) ground or any of the filter cap (C1-C3) grounds have separate ground points when replacing caps in the MRA5 amp? What would be the basis for the concern of increased hum if these grounds are all on a common buss?


Ron Rich
Forum Moderator
Posts: 8193
Joined: Sun May 06, 2007 11:31 pm
Location: Millbrae (San Francisco area)CA, USA

Re: Seeburg MRA5-L6 ground buss

by Ron Rich » Sun May 22, 2016 4:10 pm

Steve,
I have never had an problems with this--just hook the new caps up egg-zactly the same, electrically, as were the old ones.
Use caution on the "Hum Control". Clean it only with a "safety solvent", then treat it with Deoxit--or, Do not TOUCH ("adjust") it at all ( they tend to catch fire when "adjustments" are made when they are dirty--On this control, if it still won't eliminate hum, remove the ground, and use a larger wire to attach it to the transformer grounding lug. Ron Rich

Who is online

Users browsing this forum: MSNbot Media and 11 guests

It is currently Thu Oct 06, 2016 7:11 am