Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: zephyrblau on August 07, 2023, 08:53:47 pm

Title: 5B6 build using P15N vs field coil type
Post by: zephyrblau on August 07, 2023, 08:53:47 pm

first off I am a paint-by-numbers guy. I know just enough theory to be dangerous. I *do* know which end of a soldering iron causes the most pain. I know how to read and do quite a bit of that. by accident I found a similar question posted here but, didn't bookmark the page and IIRC, the issue was not resolved at least in print.
my project involves back dating a 1X15 amp to 5B6 specs for a harp player buddy. although, in several weeks of searching the 'net, I am unable to locate a single example of a 5B6 with a field coil speaker installed. the schematic calls for one. I've seen a couple of builds here and a few more @ T.A.G. but the field coil issue is never brought up. I understand that the field coil, in addition to providing a magnetic field for the voice coil may also act as a choke for the power supply.
the PT is installed in a bottom mounted Bud, the board is populated but I'm not far enough in the build to start posting voltages.
TIA




   

Title: Re: 5B6 build using P15N vs field coil type
Post by: sluckey on August 07, 2023, 09:06:05 pm

Neither of the attached files call for a field coil speaker. Is there a question here?

Title: Re: 5B6 build using P15N vs field coil type
Post by: zephyrblau on August 07, 2023, 09:21:12 pm

apparently I'm not up to speed with the symbol for a PM speaker. maybe this one is old school ?
thanks for clarifying.
I'm sure I'll have more dumb questions as the build progresses.

Title: Re: 5B6 build using P15N vs field coil type
Post by: sluckey on August 08, 2023, 08:28:11 am

Any progress on the Tremolux project?

Title: Re: 5B6 build using P15N vs field coil type
Post by: zephyrblau on August 08, 2023, 11:27:23 am

nothing so far but, thanks for asking. my "spare time" is virtually non-existent between family obligations and this project. at least for the 5B6 I have all the pieces ready to go. I'm hoping to pull the 5E9 out of hibernation, get some good gut shots and post that here as well as update the T.A.G. posting.