Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Oddvar on June 08, 2016, 11:09:40 am

Title: R4YB for GZ34
Post by: Oddvar on June 08, 2016, 11:09:40 am

Does anyone no if it's adviseable or possible to swap a RCA R4YB for a GZ34?

Title: Re: R4YB for GZ34
Post by: sluckey on June 08, 2016, 11:36:49 am

I've never heard of a R4YB.

Title: Re: R4YB for GZ34
Post by: Oddvar on June 08, 2016, 01:07:10 pm

Same as 5R4GYB

Title: Re: R4YB for GZ34
Post by: eleventeen on June 08, 2016, 02:06:45 pm

It will work, and it will not draw too much filament current. It will drop considerably more volts, about 50 more volts.


5AR4/GZ34-5DA  - 5.0   - 1.9  ->>> 17 <<<   - 250    - 450 - low Vdrop 5U4/5Y




5R4-GYA - 5T   - 5.0   - 2.0  - >>> 67 <<<   - 250    - 750 - high voltage 5U4 (ruggedized)


>>>  nominal voltage drop <<<

Title: Re: R4YB for GZ34
Post by: sluckey on June 08, 2016, 02:35:31 pm

Quote from: Oddvar on June 08, 2016, 01:07:10 pm

Same as 5R4GYB

5R4 makes sense. R4YB makes no sense. Google can't even find anything 'tube' related for R4YB.

Title: Re: R4YB for GZ34
Post by: Oddvar on June 08, 2016, 04:00:43 pm

It says R4YB on it...

Title: Re: R4YB for GZ34
Post by: sluckey on June 08, 2016, 05:17:28 pm

Quote from: Oddvar on June 08, 2016, 04:00:43 pm

It says R4YB on it...

I wonder if there was ever a 5 in front of that R4YB at some time?  :icon_biggrin:

Title: Re: R4YB for GZ34
Post by: jjasilli on June 08, 2016, 08:07:01 pm

Quote from: Oddvar on June 08, 2016, 04:00:43 pm

It says R4YB on it...

The lettering sometimes rubs or wears off.