View Full Version : 1986 Hitachi 25'' console.


Dreamsbeard
09-29-2014, 04:48 PM
Evening fellow VK'ers,

I recently picked up this nice Hitachi console television, and I was wondering if anyone could help me find the part# for the flyback? Normaly I would simply check the flyback for it but it seems the number faded/is nowhere to be found, but here's the catch : the television model and the chassis # are canadian, so they don't show in sams.

Can anyone help me ID this set?

Thanks!

PS if anyone is interested the canadian TV model is TS6460 and the chassis is G6NU2

Findm-Keepm
09-30-2014, 11:58 AM
Looks like a CT2561, based on the parts location. I have a service manual in TIFF format, 3 Megs, so it won't post here. PM me your email address if you can accept large attachments. Flyback is a 2434641.

Cheers,

Dreamsbeard
09-30-2014, 01:16 PM
PM sent!
Thanks!

Findm-Keepm
09-30-2014, 03:06 PM
Two speakers? Actually, a CT2562.

Cheers,

Dreamsbeard
09-30-2014, 04:15 PM
It's in the small details...hehe

Wait, does that means that the TV drives 2 speakers with the same amp as the 1 speaker model? Might explain why I have to put the sound setting at least about 50% of the range to have a decent sound.

Thanks! :thmbsp:

Jon A.
09-30-2014, 04:28 PM
It is actually a mono model right? If it is and the speakers are wired in series, more power would be used to drive them if the impedance of each isn't any lower than one in a single-speaker model.

Dreamsbeard
09-30-2014, 04:39 PM
Good thinking there Jon,

The speakers are actually wired in parallel (thats what I think you meant), but as you suggested, its total impedance is probably lower than the same speakers connected in series. But I think the amp still has to drive them both...so all in all if both are 5.5W , the amp has to put out 11 watts to drive them both, and only 5.5w to drive only one. Am I making sense?

Jon A.
09-30-2014, 04:58 PM
Wattage is just the power handling of the speakers. Driving them with a higher-wattage amp could blow them. It's the impedance that matters more here. Parallel wiring would halve the impedance of each speaker, so for example two 8-ohm speakers would be required for a mono circuit that requires a 4-ohm load. No extra power would be needed to drive the speakers.

rca2000
09-30-2014, 08:10 PM
I see ONLY ONE transformer-couple discrete amp in this typical 1980's hot chassis, and I DO NOT think it could produce 5W cont. The amp is near the rear of the chassis...only ONE channel. You can see it on the right side of the tuner. Those 2 sinks on the outs are NOT big enough for that sort of power. More like 2.5 W cont. And that would be consistent with many 80's model non stereo sets.

This actually looks to be older than 1986 chassis wise, more like 1982 or 83. By 86--stereo was becoming pretty popular on larger sets.

Dreamsbeard
10-01-2014, 05:35 PM
I see ONLY ONE transformer-couple discrete amp in this typical 1980's hot chassis, and I DO NOT think it could produce 5W cont. The amp is near the rear of the chassis...only ONE channel. You can see it on the right side of the tuner. Those 2 sinks on the outs are NOT big enough for that sort of power. More like 2.5 W cont. And that would be consistent with many 80's model non stereo sets.

This actually looks to be older than 1986 chassis wise, more like 1982 or 83. By 86--stereo was becoming pretty popular on larger sets.

I see, maybe this was of a sort of middle range set : 2 speakers, nicer finish, but older tech...

Dreamsbeard
10-01-2014, 06:32 PM
I see ONLY ONE transformer-couple discrete amp in this typical 1980's hot chassis, and I DO NOT think it could produce 5W cont. The amp is near the rear of the chassis...only ONE channel. You can see it on the right side of the tuner. Those 2 sinks on the outs are NOT big enough for that sort of power. More like 2.5 W cont. And that would be consistent with many 80's model non stereo sets.

This actually looks to be older than 1986 chassis wise, more like 1982 or 83. By 86--stereo was becoming pretty popular on larger sets.

So this is a hot chassis. Would you recommend that I buy an isolation transformer before I try to redo convergence on it? As you can see I am pretty new a this.

rca2000
10-01-2014, 08:04 PM
I do not suspect if has much to converge--I am sure it has an in-line tube I do not recall ANY set later than maybe 1983 using a delta tube. Even if it did--doing convergence should not require using an iso. Only of you do some WORK on it--will that be an issue, or are on a concrete floor or such while playing with the chassis.

Dreamsbeard
10-03-2014, 06:16 AM
I do not suspect if has much to converge--I am sure it has an in-line tube I do not recall ANY set later than maybe 1983 using a delta tube. Even if it did--doing convergence should not require using an iso. Only of you do some WORK on it--will that be an issue, or are on a concrete floor or such while playing with the chassis.

Well I did a quick clean and balance of the 3 guns(they where quite low and the red was smearing) and that seemed to throw the blue gun out of wack. The red and green are still properly converge, but the blue is now completely misconverged. If I remember correctly, the first two rings on the crt neck are for purity, and the others for convergence right?

The clean and balance also threw the grayscale off with a green tint, but after tinkering with it for 15 mins, it came back ok (it was perfect before). It was the first time I did a grayscale adjust, feeling proud of myself right now :D

Dreamsbeard
10-04-2014, 11:58 AM
As I was reading this article :

http://personalpages.tds.net/~rcarlsen/cbm/monitors/converge.txt

I came upon the section about convergence, and the article says that the blue gun can only be ajusted alone in an horizontal axis...is that true? As stated before the only gun needing adjustment is the blue one, and it needs to come down on a vertical axis...is there a way of only adjusting the blue gun that way, or do I have the play with the other guns as well?

Thanks!

Findm-Keepm
10-07-2014, 03:29 PM
As I was reading this article :

http://personalpages.tds.net/~rcarlsen/cbm/monitors/converge.txt

I came upon the section about convergence, and the article says that the blue gun can only be ajusted alone in an horizontal axis...is that true? As stated before the only gun needing adjustment is the blue one, and it needs to come down on a vertical axis...is there a way of only adjusting the blue gun that way, or do I have the play with the other guns as well?

Thanks!

Dunno the arrangement Hitachi used, but here's the typical magnet arrangement - the purity rings are closest to the funnel (farthest from the clamp), and then you have the two sets of magnets - aft (closest to the CRT socket) is the 6 pole, and in the middle is the 4 pole. The attached images explain it better than I ever could.

Cheers,

Dreamsbeard
10-08-2014, 08:20 AM
Wow, that's great!
Thanks!

Dreamsbeard
03-02-2015, 06:31 PM
Just a quick followup on this set ; I never had to do the convergence on it. After I "clean and balanced" it, all I did was to redo grayscale, and all the gun went back into almost perfect convergence...

I suppose that the clean and balance procedure ironicly "debalanced" the 3 guns and that might have resulted in misconvergence (great knowers here might want to correct me on that one of course :D )

Now another question : the image on the tv is pulling ever so slightly on the right, thus cutting a bit of the picture. I went around to find an horizontal centering pot, but found none. Is it possible that my TV lacks the needed ajustment to do so?

Thanks!

zeno
03-03-2015, 07:55 AM
Just a quick followup on this set ; I never had to do the convergence on it. After I "clean and balanced" it, all I did was to redo grayscale, and all the gun went back into almost perfect convergence...

I suppose that the clean and balance procedure ironicly "debalanced" the 3 guns and that might have resulted in misconvergence (great knowers here might want to correct me on that one of course :D )

Now another question : the image on the tv is pulling ever so slightly on the right, thus cutting a bit of the picture. I went around to find an horizontal centering pot, but found none. Is it possible that my TV lacks the needed ajustment to do so?

Thanks!
First, all sets are built to overscan just a little. Also these days you
gotta watch what you are feeding them.
If you got one put a cross hatch pattern up & be sure the lines are straight.
If not you have a pincushion (pin) problem.
Look for any control or jumper marked horz size, width, or lin.
If it has a horz hold move that a little.
Power supply can do it but usually causes random shut-down & other
symptoms.
If you can check the current draw. Should be about .75 amps with
a normal picture.
If there is a true problem its probably a 'lytic going bad.

73 Zeno

Jon A.
03-03-2015, 03:47 PM
I've noticed late 80s/early 90s RCA-built sets, i.e. my 1989 GE, overscan quite a bit if no signal is present. The channel display goes almost completely off the screen.

Dreamsbeard
03-03-2015, 03:59 PM
Found a jumper (horizontal cent.)that was marked : N or R , the selector was on the R pin...so I tried the N one...and that solved the problem!

Thank Zeno!

Dreamsbeard
03-03-2015, 04:06 PM
I've noticed late 80s/early 90s RCA-built sets, i.e. my 1989 GE, overscan quite a bit if no signal is present. The channel display goes almost completely off the screen.

Did not notice if the overscan was worst when there was no signal, but it was definitly bothersome on DVD/VHS signal. Glad to be rid of it!