RBM Type 55 405/625 pattern generator - UK Vintage Radio Repair and Restoration Discussion Forum

simpsons · 8th Sep 2018, 10:13 am

Being a little "nice but dim", I couldn't work out how to attach the above schematic as a private message so, for all members who have one of these beasties it is here.

One favour though, should someone have the service manual please let me know.

Chris

neil29 · 9th Sep 2018, 12:29 pm

I've yet to actually tidy the case or get my one working properly even though I've had it a fair while now.

dragonser · 10th Sep 2018, 9:37 am

Hi,
this is very interesting, thank you.
It looks a " similar " design to a Labgear E5180a. On the Labgear generator I found that some of the resistors had gone high in value.. but there seem to be a couple of other possible faults as well.

dazzlevision · 10th Sep 2018, 10:08 am

Quote:

Originally Posted by simpsons

One favour though, should someone have the service manual please let me know.

I have one of these and the TPG55 circuit, waveforms and voltages were published in an edition of Rank Bush Murphy's "Service Skill - its dealer service department update newsletter.

I have scans of the above and of the user instructions booklet. PM me with your email address and I send them to you. They are high resolution, so won't be clear if I upload them into this thread.

However, I have never come across a service manual, detailing the set-up adjustments for the many preset pots inside.

8th Sep 2018, 10:13 am	#1
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	RBM Type 55 405/625 pattern generator Being a little "nice but dim", I couldn't work out how to attach the above schematic as a private message so, for all members who have one of these beasties it is here. One favour though, should someone have the service manual please let me know. Chris Attached Thumbnails

9th Sep 2018, 12:29 pm	#2
neil29 Heptode Join Date: Dec 2004 Location: Newport, Gwent, UK. Posts: 962	Re: RBM Type 55 405/625 pattern generator I've yet to actually tidy the case or get my one working properly even though I've had it a fair while now.

10th Sep 2018, 9:37 am	#3
dragonser Heptode Join Date: Aug 2009 Location: Carshalton, Surrey, UK. Posts: 734	Re: RBM Type 55 405/625 pattern generator Hi, this is very interesting, thank you. It looks a " similar " design to a Labgear E5180a. On the Labgear generator I found that some of the resistors had gone high in value.. but there seem to be a couple of other possible faults as well. __________________ Regards Peter B