Allen.... I got the closest I could to the actual numbers....not sure what the 3 digit prefix refers to specifically but I'm glad it shed some light on the subject.. Any one have an Idea what the prefix numbers meant??????
Craig
I was thinking maybe it might signify era of ownership of the company(?)
Historically, did Kustom change hands around 1976 or '77 ?
I think some of the earlier Kustom boards from the T&R era have a 300 series prefix, right??
Muziekschuur Messages: 27 Registered: March 2010 Location: Stavenisse
Junior Member
Did you try out to place the second (optional) eq board? Or is yours equipped with this feature? Maybe for some great Rick O Sound option of some sort?
This big K bass head was not equipped with the graphic EQ.
It just has the loop-back plug which you can see in the pics above.
Anyone who works on one of these should definitely open up that plug and thoroughly clean the contacts as this is a good place for corrosion to form causing high-resistance in the audio signal path.
While I am here, I thought I would give an update on the Big K schematics that Kustomoholic sent over to me:
I just purchased a nice HP printer/scanner and I am getting familiarized with the machine.
I may also try to clean them up a bit in a graphics program.
One of the schematics is spread over two pages. I would like to join them up to allow for 11 x 17 print out.
Should I post them here or send them to a forum admin?
kustomoholic Messages: 227 Registered: March 2009 Location: Tulsa,oklahoma
Senior Member
Glad to help... I think I copied you the page of exceptions to inclusivity of schematics... they are there but not specifically listed under the tabs In the IV B section... My manual has about everything else.
Hey Craig, I have been meaning to ask you, does your manual contain the PL-4 "parts list" for the IV Bass??
It is listed in the addendum sheet you gave us.
That parts list might be helpful as reference documentation for the components shown within the schematics.
kustomoholic Messages: 227 Registered: March 2009 Location: Tulsa,oklahoma
Senior Member
Allen... That section is included in the missing sections that was supposed to be supplied at a later date.... I wish I had those supliments but alas ...no . Glad I have what I have to share even tho its abbreviated.
eaestes Messages: 4 Registered: May 2015 Location: Dallas
Junior Member
The Thermalloy/Aavid TO-3 socket insulator specs are pretty good. Check out the Aavid/Thermalloy catalog. I'm not sure whether the aluminum oxide ones require thermal grease, but their performance is outstanding. These have about 1650V standoff voltage and the higher the BTU/hr-ft°F rating, the better they transfer heat and the cooler the transistors will operate.