Bottlehead Forum

Bottlehead Kits => Mainline => Topic started by: Woid on October 15, 2013, 05:08:25 PM

Title: Low Kreg Voltage [solved]
Post by: Woid on October 15, 2013, 05:08:25 PM

Need help!

Just finished assembly and recorded the following KReg voltages:

12.2 V (normal 220V), and 10.7 V (normal 220V).

Resistances were okay except terminal 1: 23 K ohm (normal 39.7 K ohm).

All 3 tubes and all LEDS are lit.

Plugged in the amp anyway, weak but decent sounding music coming out of the left channel only.

Visually rechecked all solder joints and connection, all looked okay.

Any ideas?

Thanks!!!

Title: Re: Low Kreg Voltage
Post by: Paul Birkeland on October 15, 2013, 05:23:34 PM

It looks like that typo is persisting, I'll let Josh know.  220V is spot on there.

Terminal 1 and terminal 5 should be the same resistance.  Differences here would indicate a possible mistake in the attenuator wiring.

To mitigate this, you can turn the fine control all the way up, which essentially removes it from the circuit. 

Title: Re: Low Kreg Voltage
Post by: Woid on October 17, 2013, 04:22:33 PM

Thanks for the prompt reply.

So, I still had a problem with no sound out of the right channel.  I systemically traced all the build instructions from the beginning and discovered that I had omitted a red wire from the input switch into  the attenuator array.  I soldered the wire in and glorious sound emerged from both channels!

Lessons that I learned as a newbie:

Do not work on a project for seven hours in a row, I WILL make a mistake by doing this.

I need better reading glasses, my old eyes (58 years old!) are not what they used to be.

Even before a burn in the sound has much punchier bass and superior soundstaging compared to my old Little Dot MKIV amp. 

Thanks for all the support!