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Re: Baffles me!!

5/13/2004 9:09 AM
TheElectricMoron Re: Baffles me!!
I'l tell you straight and true that I have checked that thing every way from Sunday about ten times and cannot find anything. And I KNOW that it is just sitting there waiting for me to stumble over it.  
When I get back from AZ I will do it all again in the desperate hope that it will leap out finally. Either that or identify the source of the dark matter and feed that back into the house meter ;)  
5/14/2004 2:19 PM
Re: Fender "75" mods
I just saw a "75" for sale at the local music store for $250. I am not sure if it is original or not.  
I can't seem to find a schematic... Any help here.  
How about the price??  
5/14/2004 5:01 PM
Kevin STP

Hi Dan; I would say that that is a fair price if it is a combo.I bought mine new when they first came out in the early eighties ,those are kinda gray years for me to recall at all.I have a schematic from the Aspen Pittman book but I did find one online for someone once and had to do a bit of research to find it.I will try to hunt one down for you.  
I have put my amp through some serious abuse and it has needed only normal maintanance,never had a let down at a gig.These are very loud amps but to sweeten the sound they need some mods.All I can figure is that they tried to make a do all amp and ended up with to many compromises.Check out Harmony Central for reviews,mostly positive regarding clean sound and reliability.Good luck and I will get back with schem.source-Kevin
5/14/2004 8:14 PM
Kevin STP

Hey Dan I've got a site for the "75" schematic- think its Duncans amp pages.Schematic Heaven has them also-Rock On
5/15/2004 4:24 AM

Found it.. Thanks!  
Questions: How is working on the amp? Circuit board laid out okay? How about the half power switch? It looks like it reduces the B+ to the output tranny and changes the Bias voltage. Is this correct? What is the B+ at when set to LOW power? Thanks again!! Dan
5/15/2004 9:55 AM
Kevin STP

Dan; The chassis is much like an older fender,black fiberboard and point to point wiring.You are right the half power switch reduces both the B+ and the bias.On mine the full power is 500vt and low power is 256 vt.The trannies are mighty big right up there with my YBA1 Traynor.No printed circuts in this amp.The one draw back is that the chassis is really crowded with parts.Real nice reverb,long 3 spring tank,but the reverb almost dissapears in the lead mode.I understand that half the reverb circut becomes part of the lead drive.My biggest complaint has been that now and then when switching channels from clean to lead the amp goes to full volume no one has come up with a solution for it.GP mag did a comparison a while back between,the 75,a Jim Kelly and one other amp and the fender faired well.When they measured output they came up with 85 watts for the 75 in High power and around 15 or 20 in low power.Hope this helps  
5/15/2004 3:34 PM
John G
For correct operation the supplied f/sh HAS to be connected(or operating correctly), other wise you get both chs at once.  
John G

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