So after this one your never gonna touch another TV again.... ever ????? :saywhat:

Stop making excuses for not investing in your hobby, screwdrivers & wire snips only go so far..... :rolleyes:

I bit rough but.....
We went out to a rib joint last week. I got a full rack & my squaw got
a half. It was a great feed & leftovers I measured my rack & it was
16" long. Next day I finished mine then the next day I took a dump and
it was just a memory. Nothing left but the CC bill.
A nice meter will usually last a lifetime unlike the ribs. Here today, flushed
tomorrow.......
So anyhows get the H OSC going FIRST ! The PS voltages are probably
a red herring.
And YES take a few days off. When we got a dog it got put aside & usually
another tech got it & fixed it fast. That tech was often the shop idiot !!

73 Zeno:smoke:
LFOD !

Unless you sell all your tube electronics or stop using them permanently you will encounter another problem where having a scope will be helpful. Test equipment is the one thing I'll probably never sell even if I were to dump 95% of my collection...I know if I sell it, a week later I'll need it bad enough to regret letting it go.

Dealing with this without a scope is like trying to win a marathon when one of your legs just got amputated yesterday and replaced with a peg leg... Dealing with this with a DMM that isn't sufficient for the job is like running that marathon with only one leg, and that leg is the peg leg...

That said if your meter has a dedicated DC Volts setting you can measure DC current as a voltage if you have a power resistor of a known value. Connect a 1 ohm or 10 Ohm power resistor in series with the cathodes, clip your meter across the resistor and measure DC voltage. DC current will equal measured DC voltage divided by resistance of that resistor...A 1 Ohm will make the math MUCH easier.

The shop idiot was a rotating position, Everyone got to be it at least once........

Same with Shop Genius....

Smoke a few high dollar Horizontal Output Transistors and your title changes fast!


.

Scopes are a funny thing. Up till the late 70's we almost never used them.
Then they became indisposable on new sets. So much so we started using them on old sets instead of plugging at them with a Simpson 260 or
RCA volt-ohmist. I thing almost any tube set can be fixed with a good meter
and a ringer for yokes & FBT's. It helped we bought the Sencore suite
then another all on crash carts. New stuff took the fustration out of
test leads etc. Sencore also used to publish a LOT of how to stuff
that was of great help.
Anyhoo time to finish my ale & hit the sack. & GB all my VK friends.

73 Zeno:smoke:
LFOD !

While I didn’t get an exact ma from L54 it does measure up perfect in ohms the ma would show higher then 580 if the voltage is being pulled down so obviously voltage is being pulled down and obviously affecting the horizontal oscillator so if everything I check from coils and resistors check good there is ceramic disc caps so if there is one leaking to ground back feeding another circuit causing this problem how can I get an idea if stray voltage is making it to ground. Is there a way to check ground in such a way to see if there is voltage there that shouldn’t be there.

In all the many sets I have restored, 10+ (lost count now), I have only had one occasion of an horizontal output tube red plating, ( Magnavox ), and this was due to a defective damper.
Truth is, you have picked a rather hard set to work on, even for experienced vintage TV buffs.

The dual horizontal outputs is a perfect example of this, not sure why Moto chose this over a single larger tube, because it only make it more complicated.
If you have not done so already, it is highly recommended that you get a matched pair of 6JM6s, where this is not critical, it will insure that the horizontal output circuit is working at optimal efficiency.

Yes I got 2 new RCA tubes and one started to red plate but I pulled the plug. So if the damper is bad would it pull the voltage down along with red plating a tube. I have a new damper I wasn’t able to check the one in the set. The only other thing I found that I missed was a 25 v150 uf cap to the contrast and brightness but it checks at 223 uf so I’m changing that one. It seems once chassis is in and the convergence and tuner are plugged in then the voltage drops but the convergence is low voltage don’t think it would pull b+ down the way it is.

New does not necessarily mean matched, though you may have difficulty finding them, they are sold in pairs that have been tested to work well together, no 2 tubes are exactly alike, and it prob won't matter THAT much, but in a situation such as this, it is always better to use a matched pair over a non-matched.
Like sold here.
https://www.vivatubes.com/nos-matche...uum-tubes-100/
out of stock :(

I had the last of the 28 tube Motorola's, the ETS908. We ran the set 5-8 hours a day! It only required a few tubes, here and there and never any circuit work.
It lasted about 10 years, used until the 23EG got too weak to show a decent picture. It still had the original 6JM6's.

I guess I'm just lucky that the 25AP22A in the Hoffman Colorcaster I found is in fair condition, it too originally came with a 23EG when it was new, still trying to find another tube, blue gun is weakest. :(

As it is now I’m going to look at the convergence panel which has 5 200v red caps. It also has a selenium diode don’t even know if that maybe shorted there was no smell to say it burned up but this voltage drop is when the convergence panel and tuner is plugged in. But have to check everything maybe this route will show something.

That most likely won't get you anywhere.

there is no bias going to the convergence circuits at all, it's fed by horizontal and vertical pulses from the respective transformers. No boas needed at all
the vertical output has a convergence tap on it, the horizontal shares the same feedback winding on the flyback that is used for horizontal AFC and color sync.
in fact, you can unplug the convergence circuits completely and still get HV, you will most likely see a partial collapse of vertical range.

I dont know half of what you guys know when it comes to these tvs but I don’t get why the voltage drops once they are plugged in. Can I test the selenium diode with a dvm.I have noticed that when the vertical is running you can usually here it at the yoke all my other color sets I was able to here it this one I don’t. So if the vertical is not running that maybe pulling down the b+ since there is a 385v on the primary side of the output transformer or maybe no running at the correct speed.well I know if the vertical quits then I have a horizontal line but maybe not running at correct speed.

the answer to that is no, for the most part, a DVM can not test selenium diodes, the diode test feature was made for SI/GE types which have a much lower junction barrier voltage, and thus trying to test selenium will always look bad to them.