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There comes a point where the frustration factor rises to the point where one must put something aside for a while and move on. This is what happened with my Philco 37-640. Until I can get another example of this radio, basically virgin, with which to compare it, and sort out where I screwed up, I have put it aside. I have decided to move on to the Lafayette HE-30 which I mentioned under March Finds & Losses. I opened up the case and looked inside. What a difference! This radio is going to be a pleasure to work on. Lots of wide open spaces, not too many condensers which I will need to replace, probably just the electrolytic. From the looks of things it is completely virgin. Here are some pictures of it as received.
[Image: https://66.media.tumblr.com/9cfc476e3a75...6bdfe6.jpg]
[Image: https://66.media.tumblr.com/3e1429041582...e22718.jpg]
[Image: https://66.media.tumblr.com/eac73f72df07...3667a4.jpg]
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Well laid out always intriguing some sets designed to be serviced others sets like they wanted to be impossible to work on. Paul
Tubetalk1
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Today I tested all the tubes in the HE-30. They are ALL the original tubes ! All but one tested VERY good. The audio output tube, a 6AQ5 tests very weak. I think this radio was not used very much, both from its overall condition, and from the fact it has all the original tubes, and all but the audio output tube test virtually like new. WOW ! good news. Yesterday I ordered an entire new set of tubes, plus one extra of each, but I will be able to put them aside for spares except for one of the two 6AQ5's I ordered. I like to keep a full set of extra tubes for my important radios, I put them aside in a box labeled with the radio's name. I have a feeling this one may become a favorite.
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I sure like the look (and idea) of that shielded line to and from the volume pot. I'm surprised that didn't become universal a long time before.
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Today my order from AES arrived. I replaced the 2 section main filter condenser. The original condenser was 40mfd-40mfd at 300 volts. The new one is 50 mfd-50 mfd at 500 volts. It is a perfect fit using the original clamp, contacts fit exactly the same through the chassis hole. My tubes arrived too as part of the order. I will do a test on it later this evening, when reception is better. I am waiting on a 470 ohm 3 watt resistor to replace a 10 mfd electrolytic with a 1 watt 470 ohm resistor across it attached between chassis and the cathode of the audio output tube to create bias, but it may not be necessary. There are a few other electrolytic condensers in the set, all small values that one now uses poly caps to replace, which I will leave until after I give the set a test, and only replace if there seems to be a problem. They all look fine, no bulges or other signs of a problem. Here are pics of the new condenser installed...
[Image: https://66.media.tumblr.com/a93214783efb...5c4be9.jpg]
[Image: https://66.media.tumblr.com/999cfd5c3fc2...c268bb.jpg]
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There was a .01 mfd electrolytic condenser from one side of line to chassis ground. I replaced it with a .015 safety condenser, and added another between chassis ground and the other side of line for good measure.
[Image: https://66.media.tumblr.com/2b49d5a0e97d...533f15.jpg]
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I have too many SW receivers already, but am still keen to have a valved/tubed example. I don't have room for one of the real boat anchor sets, but something this size might work OK I'll be interested to know what you think of it when it is up and running.
Cheers
Ed
I don't hold with furniture that talks.
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LOL, Ed, About half of my antique receivers are shortwave sets, ranging from the Olympic 6-608- 110 and RCA 5Q55 through Philco 37-360 and 48-482, to my RCA 18T and RCA T8-18, and, top of the line, my Hammarlund HQ-140X and HQ-145. Tonight I tested out the Lafayette HE-30. I am very pleasantly surprised. The only thing that does not seem to be working as it should is the S meter. When the set arrived the movement had come loose from the front part of the meter, and I had used tape to hold it back together. I removed the meter and rang it out for resistance, and it seems to be within what I would expect, about 110 ohms. I have also put a milliamp meter across the leads which go to it, and the current varies with the signal it is receiving. Tonight I made sure the needle has free movement, and glued the movement back to the clear front part again. It is sitting drying right now, and I will re-install it tomorrow. Hopefully it will now work OK, otherwise I will have to be on the lookout for a replacement. Aside from that, I am VERY happy with this set. It works like a champ, certainly on par with my RCA T8-18, which is the best of my really old sets, if not even better. I will know better when I put the top and bottom covers back on, and test it on my outdoor antenna. The circuit is very nice, with two stages of IF amplification, and tuneable IF gain. I am also pleasantly surprised because I do not think I will have to do any alignment at all, the frequencies seem to be spot on. With just my short (6 foot piece of wire) test antenna CHU Canada at 3.33 Mhz (only 3 Kw), and WWV at 5 Mhz (10 Kw) come in very well, which makes me think this set may end up outperforming anything but my Hammarlunds. It may replace my RCA T8-18 as my daily driver.
(This post was last modified: 03-25-2020, 10:23 PM by mikethedruid.
Edit Reason: spelling
)
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Hooray ! I have re-installed the S meter and it is now working as it should. Tomorrow I'll button up the case, and test it out on my outdoor antenna. I may yet tweak the alignment to get it just right. The stations are ever so slightly off on the AM broadcast band, maybe 10 Khz, which may mean the IF has drifted slightly from age. We'll see. I won't do anything if it performs as well as it promises to. I have learned to leave well enough alone.
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Tested the HE-30 on my main antenna tonight. Ir works OK, but could be better. My RCA T8-18 is actually more sensitive and just as selective. The frequency shown on the dial, versus the station received is a little off. For WSM, 650 AM, the dial shows between 660 and 670. So, I am going to try to crisp up the alignment and see where that gets me. Also, the S meter still does not seem to be working as it should, although the meter movement itself seems to be OK. It goes up and down with the zero adjustment. That's another thing I need to play with.
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Never under estimate the effects of operator error. I carefully re-read the manual regarding the S meter and its operation. Turns out one must have the "selectivity" control all the way clockwise until it clicks into the AM-CW-SSB position for the meter to work. It also has to be there for the radio to actually work well at all. Once there, the radio REALLY comes to life. Didn't haver to touch the alignment. I was AMAZED at how many stations it receives ! Every 10 Khz on the broadcast band you hear at least a slight swoosh, and 99% of the time you hear a station. I am very pleased! The manual is not really as clear as it could be. I had read it before, but that fact did not register. here is a link from BAMA to a PDF of the manual, for those who want to see all the documentation on this radio. http://bama.edebris.com/download/lafayett/he30/he30.pdf My final opinion, except for my Hammarlunds this is the best receiver I have. Definitely my new "daily driver."
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A Ok, a real happy ending. Just get one radio shipped in a single piece to your house is a victory, you hit as Homer. Paul
Tubetalk1
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" . . . one must have the "selectivity" control all the way clockwise until it clicks into the AM-CW-SSB position, . . ."
So, let me get this straight.... you're actually increasing selectvity, tuning, then turning it back the other way (counterclockwise), to increase sensitivity to improve frequency response? . . . is that how it works?
(This post was last modified: 03-28-2020, 01:23 PM by Jake Blake.)
Posts: 1,824
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Jake, this is where the manual is about a clear as mud. Read the sections on the selectivity control, the BFO, and the Q multiplier circuits. All I know is, for regular AM reception, on all bands, the receiver seems to work best with it clicked at the fully clockwise position, very strange, one would have expected the switch to be at the fully counter-clockwise position. I gave the link to the manual just above, read it for yourself. I suspect, with a lot more experience and playing with the set, I will understand and master it better, but it could be much better explained. I think it is a matter of one knob being asked to do too many things at once.
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". . . one knob being asked to do too many things at once."
Okay Mike. I'll check out the manual.
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