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Old 11-05-2018, 11:41 PM
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Silvertone 1771

Almost finished with this radio, however it needs an alignment and the given data is a bit off. This model uses two 6j5's as the translator and oscillator instead of a single 6K8. The data lists the 6K8 on the alignment, which of the tubes do I need to inject the signal into?

this is what I've been using
https://www.americanradiohistory.com...-1943-STU.pdf\

Thanks,
Zach
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Old 11-06-2018, 08:42 AM
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By translator you mean mixer right...there two types of tube superheterodyne one that uses a single tube self oscillating converter tube and and the other that uses a stand alone oscillator and a mixer to combine the carrier and local oscillator to get IF. You can inject at the mixer output. Also most superheterodynes will pass IF injected at the antenna.
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Old 11-06-2018, 11:15 AM
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It's just a typo. You inject the signal at the grid of the first 6J5, the mixer (the one the schematic refers to as translator).

This circuit gives a lower noise floor than a 6K8 mixer/osc would, so it should make a decent DXer.

I have a Philco around here somewhere using a similar circuit but with a 14AF7 instead of two 6J5s. It works very well and seems to dig right into the atmospheric noise.
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Old 11-07-2018, 12:10 AM
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Well, still no luck, It's receiving a single station at 790khz, but no others. There are other stronger stations in the area, so I believe the AVC is working. Any ideas?
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Old 11-08-2018, 01:38 PM
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Check to ensure your local oscillator (6J5 #2) is oscillating across the band. I've had tuning caps with shorts at certain points in their travel. That'll kill your local osc.
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Old 11-08-2018, 07:30 PM
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Well, it turned out to be simpler than I thought, one of the trimmer screws in the 1st IF stage seized up. It turned, however, it wouldn't turn all of the way to the end. It was just enough that it wouldn't pass a tuned signal. Fixed it and realigned it. Really a great performing set, I've been running it for the past few hours on my workbench while I work.

Not too bad looking of a set
Silvertone 1771.jpg

Interesting note, almost every resistor was +30% out of tolerance, weird to have so many like that. Almost thought it was my meter at first.
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Old 11-08-2018, 07:53 PM
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You're probably a touch far away, but see if you can't pick up CFZM 740 AM from Toronto, or CKLW 800 AM from Windsor. Both still have relatively wide audio bandwidth and should sound exceptionally good on that radio... and the triode front end will help on the noise front.

Last edited by benman94; 11-08-2018 at 10:16 PM.
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Old 11-08-2018, 08:22 PM
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Quote:
Originally Posted by benman94 View Post
You're probably a touch far away, but see if you can't pick up CFZM 740 AM from Toronto, or CKWW 800 AM from Windsor. Both still have relatively wide audio bandwidth and should sound exceptionally good on that radio... and the triode front end will help on the noise front.
Yeah, unfortunately out of range, but then again I am only using a 6ft wire indoors. I took my longwire antenna down for the hurricane season and haven't put it back up yet. This radio does a phenomenal job of handling any noise (still susceptible noisy lights) and is definitely one of the better tabletops that I've worked on.
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Old 11-08-2018, 11:22 PM
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Quote:
Originally Posted by Zsuttle View Post
Yeah, unfortunately out of range, but then again I am only using a 6ft wire indoors. I took my longwire antenna down for the hurricane season and haven't put it back up yet. This radio does a phenomenal job of handling any noise (still susceptible noisy lights) and is definitely one of the better tabletops that I've worked on.
An easier thing to do if your worried about storms/tree branches taking out your longwire would be to take the end that does not feed your radios and instead of tying the rope from the insulator to a ---- (tree/pole/building: pick one) make that rope long and feed it through a pulley that is attached to your ---- (pick one ), and put a weight on the other end of the rope to keep the wire taught....Maybe add a short section of string slightly weaker than the ant wire between the weight and end of the rope to act as a breakaway if the ant gets pulled farther than the length of the rope.

I was thinking of doing that way back when I lived in Florida, but I moved before I could do it...And an acquaintance was a bit of an asshole sabotaging one of my comparably rigged wires so anything not idiot proof was at risk.
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Old 11-09-2018, 09:19 AM
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I have a penchant for large outdoor loop antennas. You can null out an offending flamethrower when needed, and they're a little more manageable in rough weather than a long wire. Something to consider. I keep toying with building a 1 meter radius loop for shits and giggles...
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Old 11-09-2018, 10:16 PM
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I've been musing with the idea of putting up a more permanent antenna for a few months, though nothing has come of it yet. My original intentions were to run a wire from the eve of the house to some trees. The given antenna would be somewhere around 100-150 feet at a height of about 30ft. Then again, I have to check with city ordinances to see if it's frowned upon. (We can't even have a clothesline) If it's not feasible, I'll most likely put some sort of directional loop
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Old 11-10-2018, 09:39 AM
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In Florida, my neighborhood frowned on all antennas...So I put it up in the backyard a bit lower than the roof and no one noticed or complained.
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Old 11-10-2018, 04:02 PM
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I'm using an interior loop adjacent to a window. Where I live, I can put any kind of antenna up on the property. I use an outdoor roof-mounted yagi, mast amplified, for my ATSC. 20 channels! I'd love to install a beverage antenna of at least 300 meters long.
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