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Ross RGR 25 - schem / mod anyone?

Posted: 08 Jan 2010, 17:30
by lolbou
Hi there,

My lovely wife is so lovely that she played the guitar long before knowing me, even though she doesn't play anymore... She has an Epiphone Les Paul and an amp, which was stored in her parent's attic. I went seeking for it yesterday, and it appears to be a Ross RGR 25.

Nicely built (see the pic, it looks like a Cornish pedal!! :lol: :lol: ), nice sound too for practicing, but some pots are more than scratchy, even with good cleaning, and the EQ might need some alterations... I can get the pot values ok, but don't really have the time to trace it...

It features JRC4558DDs, Accutronics reverb tank, and a Tube Blaster channel (these two last features are footswitcheable)... I'd like to tweak it a bit while the board is removed for pots changing!

Does anyone here have the schem of this unit (pretty much unknown over the internet)? Thanks...

Re: Ross RGR 25 - schem / mod anyone?

Posted: 11 Feb 2010, 20:19
by borislavgajic
lolbou wrote:Hi there,

My lovely wife is so lovely that she played the guitar long before knowing me, even though she doesn't play anymore... She has an Epiphone Les Paul and an amp, which was stored in her parent's attic. I went seeking for it yesterday, and it appears to be a Ross RGR 25.

Nicely built (see the pic, it looks like a Cornish pedal!! :lol: :lol: ), nice sound too for practicing, but some pots are more than scratchy, even with good cleaning, and the EQ might need some alterations... I can get the pot values ok, but don't really have the time to trace it...

It features JRC4558DDs, Accutronics reverb tank, and a Tube Blaster channel (these two last features are footswitcheable)... I'd like to tweak it a bit while the board is removed for pots changing!

Does anyone here have the schem of this unit (pretty much unknown over the internet)? Thanks...
:applause:
cornish it is.... :thumbsup

nice story :D

boris

Re: Ross RGR 25 - schem / mod anyone?

Posted: 12 Feb 2010, 22:36
by Fuzzer
lolbou wrote:Nicely built (see the pic, it looks like a Cornish pedal!! :lol: :lol: )
:applause: :applause: :applause:

Re: Ross RGR 25 - schem / mod anyone?

Posted: 23 Mar 2010, 09:39
by Matais

Re: Ross RGR 25 - schem / mod anyone?

Posted: 23 Mar 2010, 12:02
by lolbou
Matais wrote:Hope this helps,

http://www.matais.co.uk/images/rgr25.jpg
Sure it does!! 8) 8) Thanks a lot for this lovely first post/contribution : welcome aboard! :wink:

Re: Ross RGR 25 - schem / mod anyone?

Posted: 05 Nov 2014, 16:29
by lolbou
Bump!

Anyone with that schem - properly - saved on his hard disk? Mine crashed some time ago, and I did not manage to rescue this file, and did not have a - proper - backup :slap: ...

Thanks for sharing again!

Re: Ross RGR 25 - schem / mod anyone?

Posted: 12 Nov 2014, 08:57
by lolbou
Bumpy bumpy bump...

Sure? No one has saved the bloody schem with more care than me? Pleaaase... :(

Re: Ross RGR 25 - schem / mod anyone?

Posted: 12 Nov 2014, 09:17
by deltafred
lolbou wrote:Bumpy bumpy bump...

Sure? No one has saved the bloody schem with more care than me? Pleaaase... :(
I checked my old backup drive as it is the sort of thing I would copy for (possible) future use. Unfortunately I missed that one.

Re: Ross RGR 25 - schem / mod anyone?

Posted: 14 Nov 2014, 08:44
by lolbou
Cheers! That's the kind of habit I'm after, properly backing things up for future reference. I guess I've learned the hardest way! :slap:

Anyway, the amp is pretty reliable, but still... Anyone else? :mrgreen:

Re: Ross RGR 25 - schem / mod anyone?

Posted: 20 Nov 2014, 00:47
by Doug
From my backup drive to yours...

Doug


https://www.freestompboxes.org/download/ ... w&id=25195

lolbou wrote:Cheers! That's the kind of habit I'm after, properly backing things up for future reference. I guess I've learned the hardest way! :slap:

Anyway, the amp is pretty reliable, but still... Anyone else? :mrgreen:

Re: Ross RGR 25 - schem / mod anyone?

Posted: 20 Nov 2014, 07:52
by lolbou
Thanks a bloody full lot Doug! :hug: It's already on two separated drives, with a third copy ready to have its own dropbox alias...

Thanks again! :thumbsup

Re: Ross RGR 25 - schem / mod anyone?

Posted: 17 May 2015, 20:49
by lolbou
Anecdotic bump :

The wife and I slept at the in-law's house last night. This morning, my wife decided to clear out some old stuff she had in a closet from her teenage years.

Minutes later, she came to me with a brand-new looking clear PVC envelope with mint looking amplifier owner registration card, list of all USA Ross repair centers, User Manual for most of the Ross RGR amplifiers, AND a clean and accurate print of.... the bloody schematic! :slap: I've requested it twice over the last years, and there was a cleaner than clean copy of it 8 km away from here! :lol:

My version is identical to the one online, from the circuit itself to the folding mark in the very middle of the paper sheet...

Re: Ross RGR 25 - schem / mod anyone?

Posted: 19 Feb 2018, 10:05
by Pauld35
hi does any one reading this know the model of reverb tanks these use, the part number or impedance ? Ta

Re: Ross RGR 25 - schem / mod anyone?

Posted: 23 Feb 2018, 17:10
by lolbou
Pauld35 wrote:hi does any one reading this know the model of reverb tanks these use, the part number or impedance ? Ta
Had to call my nephew who's playing the amp to practice!

Reverb in the amp is Accutronics 1AB2C1B which stands for:

Code: Select all

1 : Type 1
A : input impedance -> 8 ohms
B : output impedance -> 2250 ohms
2 : decay time -> Medium (1.75 to 3.0 sec)
C : connectors -> Input Insulated / Output Grounded
1 : no locking device
B : mounting plane -> Horizontal Open Side Down