03-13-2016, 01:22 PM
All tubes are lighting up, and since the bases are not numbered how do I number them. All the tubes have 2 large pins do they count from the first large pin going clockwise?
1937 Ford Philco car radio model F-1442
03-13-2016, 01:22 PM
All tubes are lighting up, and since the bases are not numbered how do I number them. All the tubes have 2 large pins do they count from the first large pin going clockwise?
03-13-2016, 02:36 PM
Yep, looking at the bottom of the tube, with the two large pins at the 7 and 5 o'clock position. Pin 1 is the 7 o'clock large pin and count clockwise from there. A great resource is the tube database you can find here http://www.nj7p.info : click on the Tube SQL Database, enter your tube number and click on LOOKUP
The 78 tube looks like this [Image: https://dl.dropboxusercontent.com/u/54621529/78.png]
03-13-2016, 04:03 PM
41 tube voltages 2-187 vdc, 3-202 vdc, 4-3.85 vdc, 5- .05vdc. And the 75 tube, 2-118 vdc, and 5-1.3 vdc. Hopefully this will give me a direction.
03-13-2016, 05:37 PM
Hmmmm Voltages all look good. Check spkr connections, tube heaters are glowing, that there is a cap connect from pin 2 of the 75 tube to pin 4 of the 41 tube.
Terry
03-13-2016, 06:40 PM
The cap is there on the right pins I replaced that one with an orange dip .01mfd 600V. Unless there's something I'm missing on the speaker. I'm only using 2 of the 3 connections because all I have is a modern speaker, I don't have the original which would probably have 3 wires. Is there something somewhere else we should be looking at or for?
03-13-2016, 09:46 PM
The spkr does have 3 connections. Two of them connect the output transformer(read use these) the other connection goes back to the battery and is used to power the field coil. Do not use this connection as it will make spkr look like the beginning of the Bonanza tv show. Are the 75 and 41 tubes lit??
Terry
03-13-2016, 10:58 PM
Yes both tubes are lit, I've checked the rest and they're also lit up. I've been trying to add a photo of the speaker connection on the side of the box. One connection goes to the audio out put transformer and the other 2 seem virtually the same with capacitors attached to them.
03-14-2016, 05:07 PM
Spkr should be connected chassis ground and the ungrounded side of the output transformers secondary. Out of the three pin on the spkr plug one is at 6vdc. Do not use that one other two are connected to ground and the output transformer.
Check the resistance across these two. I suppose you could have an open secondary from applying 6v across it. Terry
03-14-2016, 09:02 PM
It's ALIVE! It came right down to that speaker connection! Reception was pretty good as well! So only one of those connections is audio only and one of the others was for the electro magnet. The third one I have no idea, but through all of it it now is in working condition!
03-14-2016, 09:49 PM
: thumbup:
03-15-2016, 08:32 PM
Thanks guys for the help! On to the next project.
03-15-2016, 10:26 PM
Glad to help out!
Terry
02-17-2018, 11:37 PM
jr,
you still working on the F-1442 radio? here's a link to the aligning steps. altho, you pretty much need a modulated signal generator. readily available on ebay. here's one now, current bid $18 +S&H https://www.ebay.com/itm/Vintage-Heathki...2688421426 aligning steps: http://www.nostalgiaair.org/pagesbymodel...014000.pdf the site http://www.nostalgiaair.org has all Rider manuals. click on resources, pick your brand then your model. the third "speaker" connection isn't grounded as terry said. by a long shot. it should read 195V DC more or less. it's used to test the high voltage circuit without having to open the radio. the original speaker used a coaxial cord. the mesh outer shield was the connection to ground. the 6V outlet powered the coil in an original speaker. modern speakers use a permanent magnet in place of a coil.
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