Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TIMBO on November 14, 2015, 04:15:09 am

Title: Fi Sonic 10W Combo
Post by: TIMBO on November 14, 2015, 04:15:09 am
Hi guys, This is another amp saved from the rubbish heap.
It's in good shape and the old tubes have a little more life left in them after 40 years.
Some of the Ecaps have been replaced and are in good nic, so I replaced the cathode caps that were original.

Fired up with a motorboat sound and found that replacing the 6GW8s fixed that.
The trem had no wobble at all and replacing the 12AX7 had no effect, so tapping around the solder joints found a coldie, trem fixed.

She not too pretty under the hood, but has a great sound.
Title: Re: Fi Sonic 10W Combo
Post by: TIMBO on November 14, 2015, 04:16:12 am
SCHEM
Title: Re: Fi Sonic 10W Combo
Post by: John on November 14, 2015, 04:21:49 am
Pretty is as pretty does; if it sounds good it's pretty!  :icon_biggrin:
Title: Re: Fi Sonic 10W Combo
Post by: trobbins on November 14, 2015, 04:53:02 am
How close is the reverb circuit to the 30WGR?


I can't seem to spot an LDR and neon - are they used in the trem circuit?


PS. can you pdf the schem :-)
Title: Re: Fi Sonic 10W Combo
Post by: tubenit on November 14, 2015, 05:24:19 am
Here is a GIF of the amp.  The SCH file also contains a voltage chart.

THANKS Timbo for posting this!!

With respect, Tubenit
Title: Re: Fi Sonic 10W Combo
Post by: tubenit on November 14, 2015, 05:34:08 am
As an FYI to anyone who wishes to convert a SCH file to GIF.

Click on to the SCH & open it.

Click on to "export schematic image".   When you do this, it will save automatically as a BitMap.  Save as BitMap

Using Windows "PAINT", ......  open the BitMap file  &  resave it as a GIF

Using Windows PAINT, .....  open the GIF file & resize to "55"   (which means you are resizing it smaller to 55% of the 100% original file)

From there you can use windows paint to color things like a layout board or terminals etc......   (see attached schematic as an example)

With respect, Tubenit

Having said that ................... I wished more forum members would use ExpressSCH or j-schem.

Title: Re: Fi Sonic 10W Combo
Post by: printer2 on November 14, 2015, 07:47:18 am


Having said that ................... I wished more forum members would use ExpressSCH or j-schem.


It is time I moved to a new program instead of putzing around with what I have been using. Good thing I checked out this thread, doubt I would have thought to change otherwise.