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City: Clayton, NC
I like to do the same thing, especially with power resistors. Nothing wrong with less heat generation.
I mainly keep 1W, 2W, a small number of 3W, and 5W resistors here.
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City: Merrick, Long Island, NY
Agree but just beware it was common practice to use a marginally rated resistor in the voltage divider to serve as an erzatz fuse to limit liability. Seen this done on some pretty sophisticated sets. Save a nickel.
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City: Jackson, NJ
Candohm relied on the chassis being a heatsink. What I can't get is whether their power rating was WITH the chassis attached or not, which makes the difference.
If I knew the currents in every branch, I'd calculated that but then...
So I just went with conservative approach.
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City: Lehighton
State, Province, Country: PA
I am carefully following your cabinet restoration with special attention to the veneer issues. As soon as I have this cabinet stabilized and all the delaminations fixed I'll be digging into the actual veneer repairs.
[Image: http://i863.photobucket.com/albums/ab191...262-26.jpg]
Larry
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Larry, you sure you were talking to me and not to Gene?
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City: Jackson, NJ
Gene and Geoff,
Could you guy do me a favour?
On this radio we have there is that resistor R2. That is, there are two of them.
One is in the 6k7 cathode ad is the feedback bypassed by the sensitivity switch, whichj shorts it when you listen to remote stations.
The other is on the tone control, on the sch shown right below the volume pot abd C12.
Now, the problem is with the first one. When I decided to check it, it was too low, about 1.4K. It needs to be 47K.
I do not see how the resistor can go that low. The sodering did not look like it was replaced. The colors faded so I cannot read the stripes.
The othery resistor is 47k' or very close, as it should be according to the BOM.
So I have my doubts about the manual, possibly listing a wrong value. I replaced it, but not sure about it.
Can you take a meter top it and check the value?
You do not need to desolder, it will read the actual resistance, just have the switch set on long distance and not on Local stations.
Thanks, Mike.
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If I get a chance this weekend I'll pull the chassis down off the shelf and see what resistor's in there.
Larry
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City: Jackson, NJ
Thanks Larry.
One thing I really abhore about Zenith schematic is their ref. designator serving as value-related position and not as unique part.
They can have several R2s, or C12s in the same sch, and this is just stupid as you now cannot say "look at the R2 for me" and you have to say "look at the R2 in the 6k7 cathode."
The R2 becomes a R2, a big no-no for me. In Philcos even though all the parts are simply denoted by numbers, not by alphanumerics, but those are unique and listed comma-separated, much like it is today in BOMs.
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Well, have just finished recapping. Except the micas I took every tubular cap, drilled the guts out, stuffed them with new film caps. The old ones were totally off. Now they look good, authentic and are right values too. Will show pictures later.
Oh and most resistors are replaced also.
(This post was last modified: 06-28-2012, 11:33 PM by morzh.)
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City: Jackson, NJ
Well, today is the day of the first reward - the Zee played the local "Good oldies" station, and the sound was great.
And this is with the tone control still broken. - not even sure what it is set to.
After yesterday's recapping finished, I cleaned the tubes, which all had at least their filament intact and no obvious shorts, one of them, the second detector, said "bad" on its base, but I thought it is probably subpar but still working, at least for testing, as I still don't have a tube tester; soldered the grid cap to one of the tubes where it came off; put the rectifier in, made sure it rectified, then plugged the speaker, made sure the voltage is everywhere, plugged the rest of the tubes, saw them glow, then t oched the grid of the first stage and heard the hum. Connected a wire to Antenna, set the dial to the local station I usually listen to, and, voila, it played.
Well, I'm gonna finish the beer, then take the RF Gen. to it.
Now I have to:
- Find a new tone ctl switch
- Fix the tuning belt
- Fix the motordrive belt
- tune the IF and the dial
- The magic eye tube does not even glow green. Probably needs fixin'.
- check the SW foreign broadcast;
- Eventually test the tubes (well, just earned a little side money, enough to buy something nice, so, my love, take that!)
The audio transformer obviously is a successful choice, as it plays well and fit right in with minor adjustments.
This is it so far; will go to my main computer and post the photos of the recapped chassis.
(This post was last modified: 06-30-2012, 04:07 PM by morzh.)
Posts: 15,444
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Joined: Oct 2011
City: Jackson, NJ
Posts: 15,444
Threads: 539
Joined: Oct 2011
City: Jackson, NJ
Used the RF generator; it's amazing but the tuning, IF and bands are dead on.
Went to "Foreign broadcast" and in the vicinity of 6 MHz (oh sorry...Megacycles ![Icon_smile Icon_smile](https://philcoradio.com/phorum/images/smilies/icon_smile.gif) ) pulled China and then Japan, the latter pretty clear.
Operating the tuning with bad belt is a major PITA.
Posts: 16
Threads: 1
Joined: Jan 2012
I see you have a non zenith wax/paper cap from the back of your speaker plug to the candohm lug (where all the negative leads go from the other caps). My 9s262 chassis does not have this. I assume it was done at some point in the past to eliminate noise?
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City: Jackson, NJ
No, it is a cap that is in the sch, the C17. They obviosly changed some caps, probably way back, in 40s or 50s, there is another one that is not Zenith.
This is 0.002uF, but supposed to be 1000V, and this is 600V, and I also put 600V in.
There were some replacements done.
My magic eye tube is 6u5 and it is supposed to be 6T5, for example. And so on.
(This post was last modified: 07-12-2012, 08:29 PM by morzh.)
Posts: 15,444
Threads: 539
Joined: Oct 2011
City: Jackson, NJ
Today I put the belts in and used the motor drive. Cool as heck!
I found "Adams manufacturing radio", adamsradio.com, and the guy has belts for every Zenith model, for every part, so I ordered condenser and motor belts, and they came in four days.
At 6 bicks a pop and 70 cents postage, well worth it.
The last part, the tone ctl switch. Not sure what to do. Superglue?
(This post was last modified: 07-12-2012, 08:35 PM by morzh.)
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