Latest acquisition, Cossor 551

[John_Dw]

I picked up, on eBay, what was then unidentified, this valve portable radio, complete with a set of dead batteries.
After some research I identified it as something quite rare, a Cossor Model 551.

It was in surprisingly good condition, inside and out. Initially the only obvious fault was a detached wire from the LT battery plug so I set about removing the old cells from the two batteries that came with it, and repopulating them with new cells, two alkaline 'D' batteries for the AD35 one but could only fit nine 'PP3s' in the B126 case, so slightly down on the original 90 volts....
With these attached, turning the set on saw all of the valve filaments start to glow though the DL96 output valve seemed very dim, but alas no sign of any immediate audio . After a minute or two some low level audio could be heard on the speaker and the set tuned to Radio 5 on MW, albeit very quiet and if the volume was turned up it distorted badly. Suspecting a problem with the DL96 I checked it with a multi meter and found that there was an open circuit between pin seven and pin 5, the heater centre tap, which meant that only half of the heater was actually working.
I managed to acquire a replacement DL96, which arrived yesterday. I had previously checked all of the wax caps for resistance with a multi meter and all looked good, but to be on the safe side I replaced 'C9' the output stage grid coupling capacitor with a new 0.01uF 630v one before replacing the valve.
With the new valve in place, turning the set on produced instant audio!
As mentioned earlier the set was in very good cosmetic condition and only needed gentle cleaning to restore it to 'as new' appearance.
All in all a very satisfying job, seen in action HERE.
The apparent rarity of these appears to be due to the set only being made for a very short time as it didn't sell well, no doubt to it's appearance, the attache case version, Model 552, which used the same chassis being much more popular, selling in greater numbers.

[Cobaltblue]

Indeed not a common set it took me years to get my example.

The only thing I can see not right is it doesn't have the correct knobs.

Nice find

Cheers

Mike T

[John_Dw]

Originally Posted by Cobaltblue

Indeed not a common set it took me years to get my example.

The only thing I can see not right is it doesn't have the correct knobs.

Nice find

Cheers

Mike T

Thanks Mike, out of interest what are the correct knobs? I can find very little about this set on the internet and almost no pictures of it.... I was quite surprised to find the card disk, marked MW and LW still under the wave change knob. Was there originally a similar disk under the on/off volume knob?
The Cossor brand has a particular interest to me as I grew up and lived for my first 19 years in Highbury. My uncle, who lived with us (and is still alive, now in his late 90's) worked at the Cossor factory, though I think he was involved in radar and not the radios. Also, on leaving school in 1964 I embarked on an apprenticeship for a company called Hilger & Watts, that were based in what I now suspect was part of the original Cossor factory, namely 'Aberdeen Works' in Highbury Grove (No22?). In 1970 I moved back to Highbury and lived in Aberdeen road, which ran behind the main Cossor factory site.....

[Cobaltblue]

There are pictures on my website I have just been trying to find the files for higher quality pictures but they are the same as those fitted to the 552.

Incidentally the tuning knob on both 551 and 552 seems to sometimes have the gold coloured trim and sometimes its clear I have not seen enough examples to work out whats going on.

To me it makes sense the trim is present to hide the screws

Its not common to find the discs still under the knobs but one of my 552's have discs under both knobs.

They did the 551 in an alternative colour scheme of "tweed" green and dark green.

I will load some pictures when I find them

Cheers

Mike T

[John_Dw]

Originally Posted by Cobaltblue

There are pictures on my website I have just been trying to find the files for higher quality pictures but they are the same as those fitted to the 552.

Incidentally the tuning knob on both 551 and 552 seems to sometimes have the gold coloured trim and sometimes its clear I have not seen enough examples to work out whats going on.

To me it makes sense the trim is present to hide the screws

Its not common to find the discs still under the knobs but one of my 552's have discs under both knobs.

They did the 551 in an alternative colour scheme of "tweed" green and dark green.

I will load some pictures when I find them

Cheers

Mike T

Mike, what is the printing on the right hand cardboard disc under the on/off volume control? I have found a couple of the 'correct' knobs for the set and would like to make reproduction replacements for the two cardboard discs, as, with the correct knobs, the set will appear virtually 'as new', with no discernable age related damage at all.
John....

[Cobaltblue]

Hi John that might take a while. The 552 with the paperwork attached is in storage in Poole I am not sure when I will be going there as I am working from Exeter for the next week or so maybe longer. Unfortunate timing as I have been in the office every week since Christmas.

I will update you when I locate it. The downside of having hundreds of sets

Cheers

Mike T

[John_Dw]

Originally Posted by Cobaltblue

Hi John that might take a while. The 552 with the paperwork attached is in storage in Poole I am not sure when I will be going there as I am working from Exeter for the next week or so maybe longer. Unfortunate timing as I have been in the office every week since Christmas.

I will update you when I locate it. The downside of having hundreds of sets

Cheers

Mike T

Many thanks Mike, no immediate rush for the information, but would be a nice touch if I can reproduce new, flat, complete discs, but in a colour to match the dial paper, got some card already lined up for that
Regards John..

[John_Dw]

Latest pictures of my Cossor 551, now with the 'correct' knobs fitted, and replacement card discs fitted under them...

[crackle]

If you want to see Johns lovely example of a Cossor 551 in a little more detail (RM members) the photos are now in the Radio Museum.
Mike

[John_Dw]

Originally Posted by crackle

If you want to see Johns lovely example of a Cossor 551 in a little more detail (RM members) the photos are now in the Radio Museum.
Mike

Cheers Mike, hadn't realised that you were on here