Isn't it exciting when a small parcel is waiting, full of goodies recently ordered !
Yes it is, but the down side is I don't know when I will get to plug one in now!
Pray why dear sir? Everything stops for TV restoration ... ?
If only it did!
These days I am very limited on when I can get to the workshop. Family and work have to take priority. I was lucky last week to get a couple of days of TV time.
I went for a hunt through the sets that I can get at to see if any might have a PCF808. Luckily one did and it's from the same stable as the 3643. Anyone want to guess which one?
Jon
That would have to have been a 1400 or 950, I'm not aware of any other UK manufacturer using the 30FL14/PCF808 or could I be wrong?
Blue print too, I wonder what the Audiophools would make of them.
I went for a hunt through the sets that I can get at to see if any might have a PCF808. Luckily one did and it's from the same stable as the 3643. Anyone want to guess which one?
Jon
That would have to have been a 1400 or 950, I'm not aware of any other UK manufacturer using the 30FL14/PCF808 or could I be wrong?
Blue print too, I wonder what the Audiophools would make of them.
John.
You are correct John, it was from an Ultra badged 1400.
Judging by the price probably not much. They were just under £5 for the two.
I'm delighted you got the set. I guessed it was a later model by the conventional cabinet back in place of the plastic previously used. The dropper capacitor was removed with a more conventional warm up sequence. Chris' scan of the model includes the latter version with the comment, "The two stage warm up doesn't apply to this version".
You've been lucky with the Mazda PCF 808s. There's a foreign version which is not compatible with the 30FL14. I tried one in a 1400 which gave severely miles out line lock. It could have been faulty of course but I've never encountered problems with the ones marked 30FL14 /PCF 808
Frame troubles- Horror! I still haven't rectified the top frame disturbance fault on my Ultra despite replacing just about everything that could cause the fault. It's currently put aside awaiting another attempt at solving the problem later in the year.
The good news is access is good once the chassis is partially removed. Screws at each side of the chassis can be removed allowing the top to be swung up for access, applicable for the sound output stage components too of course.
Looks like the line output stage cover is missing from your set but as in later 950 sets it could have been omitted of course. I think it was more to protect the plastic cabinet than anything else.
The all important heat deflector protecting the sound output stage is thankfully present though. It was missing from my set so had to improvised. Still gets horribly hot though.
I wonder if the CRT is a CME 1602 in place of the original unprotected CME1601 and crude Fein bridge guard sheet?
Very much looking forward to hearing more. It'll inspire me to work on my example again.
I hope the PCF808 will be OK, I have not fitted one of the new ones yet as I'm still using the one I borrowed from my 1400. I know what you mean about the frame stage, this will need attention first and it's certainly not easy to get with the UHF tuner in the way! I will also need to trace out which components are which as the component drawings in the Thorn manual and the trader sheet are next to useless! Yes the rest of the set it fairly easy to get at.
I'm not sure this set has ever had a sheild around the line stage, there are no holes around the area for screws or anything, also the little diagram attached to your screening can is stuck to the inside of the rear cover on my set. This set is fitted with a Mazda CME1601 CRT and what appears to be some kind of rubber mask, is this the fein bridge guard? I'm not familiar with this.
Although I said in an earlier post I don't get much time in the workshop, I've been given a pass tonight.
I hope that you get some inspiration to finish the restore of your set.
I was not impressed with them but for the manufacturers they kept the costs down. Fun to replace when they were a few years old, less supple than when new but we managed with the usual words of encouragement.
I was not impressed with them but for the manufacturers they kept the costs down. Fun to replace when they were a few years old, less supple than when new but we managed with the usual words of encouragement.
With the chassis partially removed from the cabinet (front control knobs and side tuner knobs have to be removed of course), removing the screws at each side allows the top to be swung up giving good access to the Frame and Sound panels. Note the tuner knobs have screw fittings.
I would imagine the CRT fitting and Feinbridge guard sheet to be the same as my HMV here. The CRT face rests on the flat implosion sheet and secured to the cabinet by a plastic cradle.
Those dark brown rough textured resistors are notorious for changing value. You'll probably have to replace the lot of them.
On my example I'll have to replace the linearity control s. I'd already replaced the height control which had a dud spot but the plastic bodied replacement soon failed. Not the first time with these plastic types which clearly aren't up to the job.
Having problems with wires breaking off and the likes I did this diagram. I was surprised to find the boost supply to the height control lead was black and white.
Having a few hours in the workshop tonight, so I finished off identifying the components in the frame stage. I have created 3 images with component number and component values.
Well it will certainly help me with fixing the frame fault and if anyone else has a set with this chassis fitted it may be of use to them too. As for the PCL805/85 I thought they were quite common?
The fall out so far has been 100% of components checked are well out of spec.
This type of resistor can be very good or very bad, for instance I have some NOS that all read about double the value. Then, in a Stella TV set of mine, most are spot on in value. Then again, in some circuits, you would be surprised how much variation in value can be tolerated before a fault appears.
To understand the black art of electronics is to understand witchcraft. Andrew.
Those high value carbon resistors went high quite frequently, presume it was their construction, they were not overloaded.
I think the blue and the grey capacitors are mixed dielectric, could be wrong but they look like it. The only faults I had with that type was short circuit, never had them leaky, unless you judge a S/C to be a leak ? .
