Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Dudemanrod on October 14, 2025, 02:20:14 pm

Title: 5e3 start up checks
Post by: Dudemanrod on October 14, 2025, 02:20:14 pm
First build and following checks before starting. This is hoffman 5e3 turret and parts kit with no mods. Checked the ground prong to the list and everything beeps but the filter cap by itself did not and its correct on polarity. I Don't want to start it unless I figure this out. Not wanting to have a cap explode in my  face. Please help. Thank you
Title: Re: 5e3 start up checks
Post by: shooter on October 14, 2025, 03:48:53 pm
"beeps" tell me you're using continuity instead of Resistance, break that habit.


when measuring a discharged cap using Resistance, the meter should start ~~~~50kohms and quickly "charge" to near or at Infinity.
Title: Re: 5e3 start up checks
Post by: passaloutre on October 14, 2025, 03:52:42 pm
Hi Dudemanrod!

It sounds like you're testing all the ground points in your build before powering it up for the first time. That seems like a smart thing to do!

Can you show us where on the schematic you're expecting to find ground but not finding it?

Schematic is best, but even a picture or a layout would be better than just a text description.
Title: Re: 5e3 start up checks
Post by: shooter on October 14, 2025, 06:23:29 pm

Schematic is best

or just get your own copy here;


https://el34world.com/schematics.htm#Hoffman_5E3_Tweed_Deluxe_
Title: Re: 5e3 start up checks
Post by: Dudemanrod on October 14, 2025, 06:27:29 pm
Both caps on left have continuity and the one on the right nothing
Title: Re: 5e3 start up checks
Post by: Dudemanrod on October 14, 2025, 11:12:55 pm
OK I did not have a ground from the input jack connected to the board. Plus that filter cap is measured downstream unlike the front tw0 filter caps. Thank you for your replies
Title: Re: 5e3 start up checks
Post by: dogburn on October 15, 2025, 09:45:40 am
Some of that wiring makes me nervous just looking at the photo. Some of the ends of wires and leads are really close together and could lead to arcing. I'd make sure they were all nicely separated.