CR100 plus cw tx - UK Vintage Radio Repair and Restoration Discussion Forum

Mikebay · 12th Dec 2009, 4:39 pm

Hi all
I have a CR100 I am rebuilding (v. slowly!), and would like to add a modification to it. It was fitted to the mil/naval versions towards the end of the war, or just after. It was a 2 valve CW transmitter bolted under the lid of the parent set.
If anybody has any details, mechanical and electronic, they could let me have a copy of them, or even better a copy of AP63993?
Mike M0XGG

dave walsh · 12th Dec 2009, 5:30 pm

This may have been discussed on here previously and I think there was an article [and photograph] in the Radiophile Mag at one point

but don't take my word for it. I seem to recall some doubt about the concept of a CR100/B28 "TX" at first. Dave W

On second thoughts Radio Bygones I think!

jimmc101 · 13th Dec 2009, 12:26 am

There is a mention of this beast in "The Restoration of Valved High Frequency Communications Receivers" by Chris Parry
(Free download here http://www.vk2bv.org/radio/radio-fil...ook-050723.pdf)

...'The cabinet has been drilled to accept the rare post-war companion CW transmitter. Unfortunately this subassembly is no longer fitted. Rather few of these units exist nowadays. They were built for use by the 1950s UK civil defence network when training for a nuclear war. These 6V6 transmitters were very effective in use. A special small-envelope shouldered glass 6V6G was specified, but most surviving examples have an ordinary 6V6GT or 6V6GT/G fitted.'

It appears this group will supply the manual (item 854) if requested by email
http://www.royalsignals.org.uk/uk-co...lth-rx-tx.html

Jim

jimmc101 · 13th Dec 2009, 11:02 pm

Just come across a picture of the transmitter here http://www.qsl.net/g4bxd/uk.htm (just over halfway down the page, labelled 'B-28 tx')

Jim

MichaelR · 14th Dec 2009, 12:22 am

I think you will get all you want from this previous thread, some body has the circuit and the manual and there are some good pictures of a unit.

https://www.vintage-radio.net/forum/...d.php?p=229778

Regards
Mike

jimmc101 · 14th Dec 2009, 12:34 am

Thanks Mike for the link, I knew I'd seen one of these in the flesh but couldn't remember where.
It must have been at HMS Collingwood museum.

Jim

Mikebay · 14th Dec 2009, 11:13 am

Likewise thanks for the link, Mike, I have sent Graham an email.
Mike M0XGG

Oldtimer74 · 18th Dec 2009, 12:15 am

Confirm Collingwood do have one.
Pat G3IKR

12th Dec 2009, 4:39 pm	#1
Mikebay Rest in Peace Join Date: Nov 2006 Location: Leominster, Herefordshire Posts: 174	CR100 plus cw tx Hi all I have a CR100 I am rebuilding (v. slowly!), and would like to add a modification to it. It was fitted to the mil/naval versions towards the end of the war, or just after. It was a 2 valve CW transmitter bolted under the lid of the parent set. If anybody has any details, mechanical and electronic, they could let me have a copy of them, or even better a copy of AP63993? Mike M0XGG

12th Dec 2009, 5:30 pm	#2
dave walsh Dekatron Join Date: Jan 2006 Location: Ramsbottom (Nr Bury) Lancs or Bexhill (Nr Hastings) Sussex. Posts: 5,817	Re: CR100 plus cw tx This may have been discussed on here previously and I think there was an article [and photograph] in the Radiophile Mag at one point but don't take my word for it. I seem to recall some doubt about the concept of a CR100/B28 "TX" at first. Dave W On second thoughts Radio Bygones I think! Last edited by dave walsh; 12th Dec 2009 at 5:34 pm. Reason: addition

13th Dec 2009, 12:26 am	#3
jimmc101 Heptode Join Date: Mar 2009 Location: Portsmouth, Hampshire, UK. Posts: 674	Re: CR100 plus cw tx There is a mention of this beast in "The Restoration of Valved High Frequency Communications Receivers" by Chris Parry (Free download here http://www.vk2bv.org/radio/radio-fil...ook-050723.pdf) ...'The cabinet has been drilled to accept the rare post-war companion CW transmitter. Unfortunately this subassembly is no longer fitted. Rather few of these units exist nowadays. They were built for use by the 1950s UK civil defence network when training for a nuclear war. These 6V6 transmitters were very effective in use. A special small-envelope shouldered glass 6V6G was specified, but most surviving examples have an ordinary 6V6GT or 6V6GT/G fitted.' It appears this group will supply the manual (item 854) if requested by email http://www.royalsignals.org.uk/uk-co...lth-rx-tx.html Jim

13th Dec 2009, 11:02 pm	#4
jimmc101 Heptode Join Date: Mar 2009 Location: Portsmouth, Hampshire, UK. Posts: 674	Re: CR100 plus cw tx Just come across a picture of the transmitter here http://www.qsl.net/g4bxd/uk.htm (just over halfway down the page, labelled 'B-28 tx') Jim

14th Dec 2009, 12:22 am	#5
MichaelR Retired Dormant Member Join Date: Mar 2006 Location: Sheffield, South Yorkshire, UK. Posts: 1,587	Re: CR100 plus cw tx I think you will get all you want from this previous thread, some body has the circuit and the manual and there are some good pictures of a unit. https://www.vintage-radio.net/forum/...d.php?p=229778 Regards Mike

14th Dec 2009, 12:34 am	#6
jimmc101 Heptode Join Date: Mar 2009 Location: Portsmouth, Hampshire, UK. Posts: 674	Re: CR100 plus cw tx Thanks Mike for the link, I knew I'd seen one of these in the flesh but couldn't remember where. It must have been at HMS Collingwood museum. Jim

14th Dec 2009, 11:13 am	#7
Mikebay Rest in Peace Join Date: Nov 2006 Location: Leominster, Herefordshire Posts: 174	Re: CR100 plus cw tx Likewise thanks for the link, Mike, I have sent Graham an email. Mike M0XGG

18th Dec 2009, 12:15 am	#8
Oldtimer74 Rest in Peace Join Date: Apr 2008 Location: Worcester, Worcestershire, UK. Posts: 330	Re: CR100 plus cw tx Confirm Collingwood do have one. Pat G3IKR