Rough Alba
 

Some time ago my skip diving friend Alan turned up with one of his gems!
This time it was an Alba 14" with the Thorn 1591 chassis. I already have a good example of one of these and this one is rough and dirty so it went in the shed!
Yesterday I decided to give it a run to see if it worked.
I switched on the tube heater lit up but nothing on the screen, the sound spluttered into life the volume control acting as sound on or off...
Then I saw a glimmer of snow on the screen. The tube was completely knackered ! I plugged in my pattern gen and twiddled the tuner knob the tuner cam promptly fell to bits!
The tuner was loose anyway as the plastic mounts had also crumbled away. So I took it out and tuned it manually by taking the spring off the bar.
To say the tube is flat is an understatement! The picture goes negative as soon as the brightness is advanced then if the brightness is advanced any further the corners of the screen go dark. The poor old gun is so clapped that it cannot get to the corners of the screen!
At this point I decided the set was only fit for parts the cabinet is rough the tuner mountings are broken with no hope of repair and the tube is completely shot!
I decided it can go back in the shed as it is . removing the chassis and binning the rest is an option which I would have taken with a bigger set but as it's a portable little space is saved by just keeping the chassis.
So before I did I decided to try an old trick to see if the tube could be improved ! :devil:
I took the tube base off shorted the heater out to prevent possibly blowing it then I earthed the cathode took the EHT connector off held it with insulated pliers and switched on.
I played an arc around the pins for a second or two and then refitted the base and anode cap.
The (probably very temporary) transformation is quite surprising! OK it's not perfect but the picture is now watchable and doesn't go negative . the contrast is now half way but the brightness is fully up this may well be the tube still or possibly another fault...
I have kept the tuner mech as I want to practice repairing it before I do the one in my 8500 which I suspect has suffered the same problem .
The rest of the set is back in the shed!
My other Alba which is cosmetically very good has never been tested so I am going to see what the tube is like on that next, at least I have some spares if it needs a LOPT!
Fist picture is before zapping, second after, rough cabinet , broken tuner.

Re: Rough Alba
 

Interesting write-up. Unusual for a portable to have a clapped crt as most had an easy life as second sets.

I've always found the awkward styling on these 14" models hard to love, compared to the much cuter 12" versions. I think they were only sold as Alba (maroon) or HMV (posh woodgrain). I wonder why there were no Ferguson, Ultra or Marconiphone versions....

Steve

Re: Rough Alba
 

I remember these Alba sets well. I used to sell them around 1973 to '75
Despite the colour of the cabinet the Alba sets sold well.
There was also HMV and Ultra versions of the same model each with different cabinet presentation.
The Ultra model was available in white.

DFWB.

Re: Rough Alba
 

The most common reason for completely flat tubes in the 1590/91 series is a change in value of the L.T. adjust pot causing the voltage to rise from 11V to over 15v.

It rises in value and by the time the picture is showing hum bars the tube is destroyed. I had quite a number that ended their days this way. I used to fit a high quality ceramic type to prevent future problems in every one I serviced. John.

Re: Rough Alba
 

All I did to 'repair' the tuner button mechanism was to dispense with the crumbly bits of plastic & relocate the springs. Dead simple to do & requires no parts. Seems to work just as well as with the springs in their original positions!

https://www.vintage-radio.net/forum/...d.php?t=150317

I've had great success over the years 'rejuvinating' tubes. B&W & delta gun colour tubes often came up really well. Mostly done with a diy unit with a 15W pigmy bulb! Only very recently have I graduated to a B&K!

All the best
Nick

Re: Rough Alba
 

I have the HMV version of this set, it is pretty decent cosmetically (after thorough cleaning off all the paint spots & grime) luckily the tuner is fine, but the tube is a bit soft.

I will check the LT voltage next time the set is used, it does not appear to have ever seen any repairs, judging by the thick layer of dust & fluff on the chassis.
:beer:
Mark

Re: Rough Alba
 

I think you may have hit the nail on the head there! I thought when I looked at the heaters they looked a little bright. The set looks as if it has had far more use than the average portable though, the PCB is thick with dust and it's not the usual grey blanket it's really grim looking!
I remember checking and resetting the 11 V line on these sets years ago when they came in for repair I didn't know the pot changed value though!
I don't think the 14" tubes were as long lived as the 12 " generally. I can't remember seeing a "tubey" 12 " but a remember some 14" set looking a bit tired.
1100 man .Thanks for the tip on the tuner! That will save me some time I had been looking into suppliers of cup washers but I don't need to now!
I am tempted to fetch the Alba in from the shed to check the L.T just to see!
I am also going to check my other sets!
:thumbsup:
Rich

Re: Rough Alba
 

The 14" tubes did have a short life compared to the 12", even if the HT remained stable. I have the HMV version which is fair but doesn't sparkle like its smaller brother. One turned up in a scene in the film Judy on a pub shelf. Supposed to be 1966....