You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
The Feb 2025 Radioddity Giveaway Results are In! Click Here to see who won!

Reply to thread

Message

The bias circuit needs to have a fairly low resistance to ground. This is the current-return path for the tubes' grid current.

A variable-bias adjustment would need to have several Watts' dissipation rating, just as the fixed-bias resistors do that it's built with.

There's not a lot to be gained from this. 40-plus years ago radios just didn't have carrier-power controls, and adding this feature to an amplifier made sense.

If you radio already has this control, the amplifier won't benefit from having it added.

Consider also that those bias-adjust pots in the 350Z would repeatedly blow out and have to be replaced. Was one of that amplifier's most-aggravating weak links in the design.

73

[QUOTE="nomadradio, post: 658752, member: 22"] The bias circuit needs to have a fairly low resistance to ground. This is the current-return path for the tubes' grid current. A variable-bias adjustment would need to have several Watts' dissipation rating, just as the fixed-bias resistors do that it's built with. There's not a lot to be gained from this. 40-plus years ago radios just didn't have carrier-power controls, and adding this feature to an amplifier made sense. If you radio already has this control, the amplifier won't benefit from having it added. Consider also that those bias-adjust pots in the 350Z would repeatedly blow out and have to be replaced. Was one of that amplifier's most-aggravating weak links in the design. 73 [/QUOTE]

Top Bottom