New Roundie sets scored

[damen]

Originally Posted by DaveWM

check your line voltage, if you have a variac see how low it can go before the width is a problem, check the cathode current at 117vac

I had it at about 117v when I did that test and I did go down lower and the cathode current went down I will have to play with it and see how low I can go with the line current with out problems.

[damen]

Originally Posted by sampson159

is this a real zenith crt?that looks as good as it did when brand new!beautiful picture that puts modern sets to shame

Yes it is a Zenith tube with code date of 1961 and still checks like new I believe it is the original.

[DaveWM]

just a couple other things, did you check the cathode current with the beam current near zero (if the sams says that way), did you replace the HOT grid coupling cap as part of the total recap? do you have some other HOT's you can try (in case the one you have is a bit gassy) how does the the shunt tube current look (I think that one still used the shunt vs the pulse type). Do you have a scope, if so you can check the PP horz drive or use a VTVM and confirm the neg voltage.

[DaveWM]

I was doing some reading about other drains on the fly that can account for higher than normal currents. thats such a nice looking picture it seems like all the other stuff is working correctly (it mentioned the convergence board as one thing to check).

[damen]

Originally Posted by DaveWM

just a couple other things, did you check the cathode current with the beam current near zero (if the sams says that way), did you replace the HOT grid coupling cap as part of the total recap? do you have some other HOT's you can try (in case the one you have is a bit gassy) how does the the shunt tube current look (I think that one still used the shunt vs the pulse type). Do you have a scope, if so you can check the PP horz drive or use a VTVM and confirm the neg voltage.

Thanks Dave for the info I will try a different HOT and not sure which one is the coupling cap I have not checked the current on the shunt and I do not know how to use a scope but the negative voltage on the HOT was very close but it does show the plus voltage on the HOT is 135V on the sams and I get 145v there is a .15 Cap to ground I replaced there but the B+ on the other side of the 7w resistor to that pin is very close . The caps on the convergence have been replaced but I will do some more checking on that board to.

[DaveWM]

it all sounds like its real close, prob just down to tubes. If the VTVM voltage on the grid of the how is close then you are prob ok. The voltages on the sams dont always match the voltages on the service manuals, besides I think they generally say +-20%. Who knows could be difference in the kind of meters being used.

The pic is great so I would not mess with it too much other than seeing if you can lower the input AC. That is def a great set.

I generally run my sets at 105-115 if they are going to be on for any length of time. I just set them up at 115 and adj after warm up to the lowest voltage that still fills out the screen. the FLYs seem to run cooler this way, but I must add I have never sat down and tried to document how much cooler.

[marty59]

Originally Posted by sampson159

is this a real zenith crt?that looks as good as it did when brand new!beautiful picture that puts modern sets to shame

I'd be curious what the EIA code is too.
That is a wonderful looking set and how fortunate of you to score a flyback!

[sampson159]

there is something about a zenith crt.i can remember going to the box stores back in the early to mid 60s and watching the sets.the rcas looked good,admirals were pretty nice but the zenith roundies were superior.the ctc15 imho was the best roundie rca made but those zeniths!very close and depending on the look you prefer.i always thought the zenith sets had a more lifelike fleshtone.that set is a beauty and i am happy for your good fortune.just wish it were me!