Biasing a Silvertone 1484

[sixstring531]

Ok - friend needs some help. He has a Silvertone 1484 and I am looking to rebias it for him but can't find any bias pots -- is there something I don't know on these older amps? I have the equipment to bias (I do my own) but I can't find anywhere to adjust it on this old beast.

Help anyone?

 

[SatelliteAmps]

It doesn't have a bias pot. It is a cathode biased amp, so you have to change out the resistor. It's the one attached to the cathode of the power tube(s).

Is the bias way off?

 

[sixstring531]

Haven't even checked it yet - didn't want to do anything before I got all my ducks in a row. Now I know, thanks man. I love this place

 

[soldersucker]

Congrats! cool amp eh.Found mine last weekend and i'm liking it.Did you get the cab to?

 

[Trout]

It doesn't have a bias pot. It is a cathode biased amp, so you have to change out the resistor. It's the one attached to the cathode of the power tube(s).

Is the bias way off?

Hey Adam,

Do you have a better copy of that particular amp schematic?

The one over at schematic heaven is weird.
Looking at the thing it looks like fixed bias (almost) or possibly some drawing someone drew on lol
http://www.schematicheaven.com/bargainbin/silvertone1484.pdf

 

[JerryP]

The 1484 is fixed bias with no bias pot.
Jerry

 

[SatelliteAmps]

It is fixed bias. I mistakenly said it was cathode biased (I had been working on a 1471 all day, and just got them backwards in my head). Same deal as JerryP pointed out.

Trout-Sorry, I don't have anything better than that one. It's pretty crappy, and with the rats nest that is inside those amps, it just takes a bit of extra care to get it all sorted out.