Last Attempt To Find Tech To Help with Avante

[zeno]

The ABL runs off the reference pin of the tripler IIRC. Its the pin
with the big resistor & is just above ground to produce a small voltage
that varies with beam current.
With a good CRT as a rule G2 pots start to show a line at abt 1/3.
You need good boost IIRC between 800 & 1000 VDC. If thats OK
look back to to the G1 & K's. A bad boost filter will lower the boost
& leave unwanted crap on it.
I really suspect the tripler. Its the common link between the sets.
There are resistors, caps & diode stacks in them that may vary in
value from the OEM tripler.

enuf fer now, time for a beer. Or 2 or3............

73 Zeno
LFOD !

[TinCanAlley]

Originally Posted by zeno

The ABL runs off the reference pin of the tripler IIRC. Its the pin
with the big resistor & is just above ground to produce a small voltage
that varies with beam current.
With a good CRT as a rule G2 pots start to show a line at abt 1/3.
You need good boost IIRC between 800 & 1000 VDC. If thats OK
look back to to the G1 & K's. A bad boost filter will lower the boost
& leave unwanted crap on it.
I really suspect the tripler. Its the common link between the sets.
There are resistors, caps & diode stacks in them that may vary in
value from the OEM tripler.

enuf fer now, time for a beer. Or 2 or3............

73 Zeno
LFOD !

The way the tripler is in this unit seems a bit different than any I've seen before, but that could just be my limited exposure.

The trippler has an input and an output. The red output goes to the suction style cup on the CRT. That connection at the CRT has a second pink lead that goes from there down to a plastic distribution block. It then breaks out to two more leads. Once goes to the focus and the other attaches somewhere around the flyback and I believe then routes to the CRT socket. I could be a little off here as I haven't opened the set for a year and I won't be for about a week or so.

[TinCanAlley]

Originally Posted by zeno

The ABL runs off the reference pin of the tripler IIRC. Its the pin
with the big resistor & is just above ground to produce a small voltage
that varies with beam current.
With a good CRT as a rule G2 pots start to show a line at abt 1/3.
You need good boost IIRC between 800 & 1000 VDC. If thats OK
look back to to the G1 & K's. A bad boost filter will lower the boost
& leave unwanted crap on it.
I really suspect the tripler. Its the common link between the sets.
There are resistors, caps & diode stacks in them that may vary in
value from the OEM tripler.

enuf fer now, time for a beer. Or 2 or3............

73 Zeno
LFOD !

Okay, so it seems I didn't change the tripler. I remember now, after finding it in a box, that it didn't match what was in the set. The one in the set has an input, ground and output. The replacement has an input, ground, focus, CTL and output. I remember hearing a sizzling sound and it was coming from the plastic piece that is fed off the anode on the CRT and then it feeds the focus and???? Anyway, I found a new one of those and installed it and the noise was gone and I just assumed the tripler was working properly. So if NTE526A isn't the correct one, what is? Or, am I supposed to do away with that plastic piece with all the connections? I've attached a pic of the current setup, but note the plastic piece in the pic is the old one. I couldn't find a current pic. The tripler pic is one I found on the web, but it is the same.

Thanks

[zeno]

The replacement shown has the focus built in.
It is not a direct replacement at all but could be moused.

The OEM ? in the set uses the divider resistor, the plastic part
with the other big red wire etc.
If you go further with it get the ##'s off the tripler. If a ZENITH
OEM you should find part number 212-141-## on it.
Also be sure that big resistor isnt burned. Bad triplers sometimes
burned it.

73 Zeno

[ed857]

Could that be a ECG 500A with the Zenith focus block ( HIDIV 3? )?

[TinCanAlley]

Originally Posted by ed857

Could that be a ECG 500A with the Zenith focus block ( HIDIV 3? )?

According to the service manual, it is 212-142-01. This one is noted as tripler only. The other part number is 212-141-01 and is the tripler with focus bleeder combined. It says to see schematic, but the schematics show the combined tripler, which is not my setup. Either way, most cross-references I can find point to the combined (NTE526A). I did find a site that has a PDF of and old Zenith list of universal triplers and it has (977-46) as the simple tripler replacement. No such luck finding that.

So I either install and ditch the external focus divider, use it with the external divider by ignoring the outputs on it, or I continue my search.

[TinCanAlley]

Originally Posted by zeno

The replacement shown has the focus built in.
It is not a direct replacement at all but could be moused.

The OEM ? in the set uses the divider resistor, the plastic part
with the other big red wire etc.
If you go further with it get the ##'s off the tripler. If a ZENITH
OEM you should find part number 212-141-## on it.
Also be sure that big resistor isnt burned. Bad triplers sometimes
burned it.

73 Zeno

I will attempt to find the part number on it this weekend. It seems, according to the service manual, that there are two different units. One with the built-in divider and one with the external. The SM shows the integrated unit, but notes there are two different ones.

So I have choices, I can try to keep it original and find one that uses the external divider, use the one with the integrated divider, or if possible, use the one with the internal divider, but don't use the integrated part and run the external divider.

Thoughts?