By now most of you are familiar with the little 13 inch color TV I got from AST
back in the late 1990s. I’ve even shown how I modified it to accept RGB input,
which means I can use it as a monitor for a whole lot of 1980s computers. In fact,
recently I’ve been using it with my Amiga to test Petscii Robots. The little TV has about the
same quality image as my Commodore 1084 monitor when connected to an Amiga, it’s really amazing.
So this little TV has been like a real trooper. I’ve been using this thing at least an hour a
day for the last 24 years and it still works perfectly. So, it’s a great, reliable little TV
to use as a monitor. Now the thing is, I wouldn’t normally be interested in having like a collection
of these or anything like that. In fact, I normally only keep like 1 of each type of monitor
around. I keep like a CGA or digital RGBi monitor around, I keep a color composite monitor, which is
this, and I keep usually some sort of monochrome composite monitor around for various things. And
I usually share these same monitors between all of the different systems that I play around with.
So there’s really not any need any more than that. But after my brother opened up his little shop and
we kind of dedicated a little museum room, plus we started having meet ups and stuff like that,
disk copy parties and things like that, where suddenly I’m like “I need, you know, a couple
of extra monitors, you know composite monitors of some kind.” So, my father-in-law actually worked
at AST as well, and I asked him if he still had his TV. And he did. He had it up in the attic,
it had been sitting up there a long time and he gave it to me and well next thing you know,
I got two of them. And then. This one actually worked fine too. And then
just a few weeks ago somebody offered me yet another one that also came from AST
and here it is. So now, I got three of them.
Unfortunately, this one doesn’t quite work right. We’re going to see if we can fix it.
So, I powered it up and got the usual static. There are no TV stations to tune this thing to
anymore. But this certainly looks like everything is working. Also the menu buttons are working. So
that’s also a good sign. But here’s where I ran into a problem. I connected up a composite video
source to the front panel and got…. nothing. I found that if I jiggle the cable just right I
can get a picture. So I’m guessing the inputs are damaged. Somebody probably tripped over a wire
or something and yanked the connectors. No big deal, let’s try the ports on the back. Fun fact,
this TV would have had a SCART connector in this spot in most other countries. That’s
why the opening is shaped the way it is is. Unfortunately, I don’t get anything
from the rear ports. Even if I jiggle the cable, I still get absolutely nothing.
That’s unfortunate that both inputs are broken as that’s the most valuable part of this TV.
So my plan is, I’m going to take this thing apart and try to fix the inputs. If they are
damaged beyond repair, I figure worst case I can drill a new hole somewhere and put a new
RCA jack on it and solder the cable straight to the board. But let’s not get ahead of ourselves.
So, let’s have a look at these rear inputs first, as they’re easier to reach. In fact, let’s flip
this upside-down so it’s easier to read. So these two pins here are ground, which is pretty obvious
from the G. And then likewise this is audio in and video in. But what about this pin? Well,
this is a switch that lets the TV know if you have inserted anything in the video port. Normally it
connects to ground, but when you insert the RCA connector, it breaks this connection.
So, it’s pretty easy to test all of these connections. I even inserted a cable so I
could test the switch. Everything seems perfect and thus I’m a little baffled.
But then I had a hypothesis I wanted to test, so it’s a good thing I had a working TV just like
it I could use. So, I want to plug a video source into the back of the ports and then
see what happens if I plug just a loose cable into the front port. And sure enough,
it appears to override the rear port, even though there is no signal present on the cable. So,
it’s possible the rear port of the TV works fine, and the whole problem is just the front port.
So, having a look down inside, it appears the front inputs are on a little separate PCB.
My first thought would be to just unplug the little board and see if maybe the TV
will work with it unplugged. Of course if it follows the same design as the rear port,
with the circuit being closed, then that makes it unlikely.
So, I tried plugging in the video source to the rear ports with the front disconnected. But
unfortunately, this didn’t work. So, the next step was to remove the little PCB so we could
have a look at it. At this point the worst case scenario is that I solder a jumper wire
so that the TV thinks the front port is not in use, and then I can just use the rear ports.
Anyway, here’s the little board. And having a look up close, it’s pretty clear what the problem is.
Every single solder joint to the RCA jacks is cracked. This is definitely the result
of a wire being yanked or tripped on or something. Wow, look at that piece!
Well, I don’t see any other specific damage so I guess I will attempt to reflow these connections
and just see what happens. I noticed this one actually has part of the trace on the
board broken off. But it appears there is enough left on the other side that it should be fine.
I guess that means it will never be quite as strong as it was before,
but I tend to be gentle with my equipment, so I’m not worried.
Now what I”m going to do is just reattach the PCB and let it hang out of the side of the TV.
This way I can test it before mounting it back inside. So I’ll just plug my video source back
in. And lookie there! It’s working. And I’ll even jiggle the connector a bit to see if it is stable.
And so now I want to test those rear ports. And I noticed when I unplugged the video source,
I’m seeing this message on the screen which I didn’t see before,
so I think that’s a good sign that it knows the cable was unplugged. And now I’ll just
plug into the rear ports. And, much as I suspected, it works perfectly as well!
Now all I need to do is re-assemble everything.
And now it’s time to test it out with some games. Both front and rear inputs
are fine. The picture on the screen is perfect, just like the other 2 I have.
Granted, this one doesn’t have RGB inputs, but I suppose I could always mod it if needed.
Also, I only have one remote control between all 3 of these TVs. And the remote is needed to access
the service menu which will let you adjust the picture, which is necessary on some
systems like my Mini-Pet. Cosmetically this is a good match for my Mini-Pet. In fact,
it’s a great match for any black computer, such as the Plus/4, or even my Bell and Howell system.
Although these do look identical, there is one slight difference that I noticed,
which I think you’ll find interesting. Notice that on the power button here there’s a little symbol.
Showing that the, you know, the little power symbol. And you look over at the others,
and it doesn’t have it. And I think the reason is because this unit was operated primarily with the
remote control. Where these two have been used a lot in person where pushing the buttons and I
think we’ve rubbed the symbol off of the button. Also looking at the back of these, One interesting
thing is that if you look at the serial number here on this one, it’s only less than 300 off
from the serial number on this other one, so that’s pretty cool.
OK, so clearly I got lucky with this one. This was a super duper easy repair. But you know, I
wanted to mention that because you know, sometimes we get old electronics in and they’re just really
really difficult to repair. And I’ve even run into a few myself where I’m just like “nope,
I’ve got to say I’m done with this because it’s just too darned difficult.” But at the same time,
quite often things like this do wind up being super duper easy to repair and a lot of people
just don’t even bother to try. And so, this is just like a little lesson. I didn’t even need any
parts to repair this. It only took like an hour’s worth of labor and it’s all working perfectly
again. So, anyway, It’s just a point that a lot of this kind of stuff that some people think is
a lost cause, it turns out it’s really not that hard to repair. So anyway, it can go both ways.
But, I guess that’s it for this episode. Kind of short I know, but as always thanks for watching!