Hoffman Amplifiers Tube Amplifier Forum

Other Stuff => Solid State => Topic started by: goldtop1 on March 13, 2010, 11:15:31 am

Title: Booster relay wiring ?
Post by: goldtop1 on March 13, 2010, 11:15:31 am

Hello fellow amp builders!
  I finished the SH-11 amp of CraigB's layout. I used the West 15 watt transformer set. The voltages were a little high so I replaced the SS rectifier to a 5AR4. No problem there. Since the original layout used the 5V side to power the relay, my question is how would I wire the relay up to the heater side{6.5} Volts without using the heater centertap? The 5V side doesn't have a CT right? If I hook it up using the heater with the CT to ground would I fry something? A layout or a schematic would be helpful! This is a great sounding amp by the way!

Title: Re: Booster relay wiring ?
Post by: ampgeek on March 14, 2010, 11:24:45 am

I am not familiar with the SH-11 plan.  Specifically, the relay configuration.

But....Weber sells a relay kit that does support a filament heater CT connection.

Check out the "CHANSW-1-LP-Kit" here:

https://taweber.powweb.com/store/chansword.htm

I poked around at bit but couldn't find a layout or schematic unfortunately.  The pics and descriptions found at the link above provide a little more insight.  I am sure that the forum folks over there could point you in the right direction too.

Hope that this helps!

Good luck,
Dave O.

Title: Re: Booster relay wiring ?
Post by: goldtop1 on March 15, 2010, 04:48:52 am

Thanks for the reply ampgeek! I also found this on the Hoffman site. #3 is exactly the same board set up as the SH-11 amp except for the 47R resistors.And also since my West PT has a CT on the heaters, I just disconnect it from ground because the relay board has a artificial ground using the 47R resistors.I also may change them to 100R like the diagram! But it works fine like it is with 6.15V coming off the board to the relay.