GEC McMichael
Model: 2290H
Year:1983
System:625 Line
Features: Teletext
Original List Price : £000.00 ( to be ascertained)
Valves: None
Transistors: Yes
Integrated Circuits: Yes
This is a recent addition, in immaculate condition. I powered it up and it instantly came on. My first observation was the raster seemed rather washed out, I expected to see the usual no signal static snow. I then connected a test signal and started tuning in. At which point there was a medium loud PHUT….. and a plume of smoke.
I believed this was the across the line mains filter cap expiring, as the set continued to happily work and the smoke soon dissipated. When I checked, indeed it was one of those RIFAs.
I continued to tune and eventually found a very poor rolling picture of the test signal.
As I suspected, the washed out blank raster I first saw doe indicate a fault. The brightness, contrast and colour controls appear to have no effect on the picture. Looks like I have a fault in the brightness circuit.
I checked the voltage out of pins 11 and 7 of the TDA3561A, they were correct. I also checked the brightness control varies in voltage swing, it does low is 1.7V and high is around 7.5V
GEC McMichael Full Circuit; Click on Image To Enlarge, Then Click Again To Zoom
Update
I spent a couple of evenings looking at this with John, scoping the various pins of the TDA3561A, and replacing as a matter of precaution 3 caps most likely to cause fault, (they were innocent) .
All is pointing towards the TDA3561A being at fault, which seems unthinkable. These ic’s were so reliable back in the day, but we are talking 36+ years later, so I guess it cannot be ruled out.
As Sherlock might once have said, “When you’ve eliminated all the probable cause of your fault, what remains, however improbable, must be the cause.”
Watch this space!
Well, after 37-years I guess anything is possible, and we have to rewrite the book on reliability of once bulletproof components. The TDA3561A had developed a fault, a replacement fitted and normal service is resumed.
Components replaced
Further Update
The remote control for this set had long been lost, however, I could not believe my luck. I looked on eBay and there was not only one but two GEC McMichael remotes up for sale. One was ratty, with most of the control identifiers rubbed off. The second, was in pristine condition, so I shelled out £25, and it arrived today, and it works. Now I can at least access Teletext functions as well as all the usual TV options.
The TV is now complete, I also have almost the exact stand it would have come with and a GEC McMichael CED disc player to go underneath. I’m very pleased with this and the repair, it will make a nice addition to the 80s section of the museum.
Nice one, looking good. I never worked on one of these, it looks like a nice repairable layout.
Nice GEC Hitachi
when I first saw this I thought it was a genuine old GEC bit disappointed to find its an Hitachi but I suppose these are getting collectible too now
we’ll done with the repair
I’m wondering if this a little earlier as it has the 4th channel button labelled as ITV2 rather than Channel 4.
Correct, I recently checked the GEC Mc Michael brochure for 1983, and this TV was listed. Thanks for the kick to check.
A former neighbour and family friend (sadly now deceased) used to work at Osram-GEC in Wembley. He had a GEC McMichael TV that looked just like this one. It was a leaving / retirement present from GEC.
It was still in use until the year before the digital switchover in 2012. He was telling me that he would need to buy a new TV, but I said no, you can go on using it with a Freeview box. I even brought a Freeview box with modulator to his house to demonstrate. Unfortunately I couldn’t get a Freeview signal. His analogue TV reception was rather snowy. I suspected a problem with his aerial or cable but couldn’t fix it.
Next time I visited a few months later, the old TV had gone. He had a brand-new flatscreen TV with Freeview, all working. He told me that he bought the new TV first, but of course that didn’t receive Freeview either, so he then called an aerial installer and paid around £200 for a new aerial. A rather expensive upgrade! And he also said he missed the teletext service on analogue TV, commenting that the Freeview teletext service was much more limited in what it offered.
These sets are interesting but I am also interested in slightly earlier GEC teletext sets. Nice to see something that blends both GEC and Hitachi.