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A Philco 38-690 Restoration
#15

April 15-16.

I decided to rebuild and use the 38-116 RF unit instead of the 38-690 RF unit.

Why?

The 38-116 RF unit had unmolested tube shield bases.

I began the long, drawn-out process of removing one section of the RF unit at a time, replacing capacitors and resistors as I went. The main sub-base of the RF unit (where the tube sockets are attached) were also rewired...which took quite a bit of time.

Remembering my experience with my 37-670, I decided to replace everything...including mica caps.

[Image: http://www.philcoradio.com/images/phorum...90_055.jpg]

I replaced the original micas with new silver micas, or with NP0 (C0G) ceramics.

[Image: http://www.philcoradio.com/images/phorum...90_056.jpg]

In the case above, capacitor (19) was 130 pF. So I connected a 120 pF and a 10 pF in parallel to obtain 130 pF.

When this section (the middle section) was finished, here's how it looked:

[Image: http://www.philcoradio.com/images/phorum...90_057.jpg]

[Image: http://www.philcoradio.com/images/phorum...90_058.jpg]

Now have a look at the oscillator section of the RF unit before I did anything to it.

[Image: http://www.philcoradio.com/images/phorum...90_059.jpg]

[Image: http://www.philcoradio.com/images/phorum...90_060.jpg]

[Image: http://www.philcoradio.com/images/phorum...90_061.jpg]

[Image: http://www.philcoradio.com/images/phorum...90_062.jpg]

[Image: http://www.philcoradio.com/images/phorum...90_063.jpg]

Coil (37) was bad. Notice the greenies in the middle:

[Image: http://www.philcoradio.com/images/phorum...90_064.jpg]

I checked the same coil in the 38-690 RF unit and, fortunately, it had good continuity! So I carefully removed it from the 690 RF unit and installed it in the 116 RF unit.

[Image: http://www.philcoradio.com/images/phorum...90_066.jpg]

While I was working on the RF units the evening of April 16 (my birthday), Debbie provided a very pleasant interruption:

[Image: http://www.philcoradio.com/images/phorum...90_065.jpg]

H B 2 Me! Icon_biggrin

--
Ron Ramirez
Ferdinand IN


Messages In This Thread
A Philco 38-690 Restoration - by Ron Ramirez - 05-25-2018, 10:50 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-25-2018, 10:53 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-25-2018, 11:04 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-25-2018, 11:11 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-25-2018, 11:14 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-25-2018, 11:19 PM
RE: A Philco 38-690 Restoration - by Arran - 05-26-2018, 02:26 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 08:20 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 08:25 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 08:31 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 09:03 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 09:31 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 09:49 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 10:02 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 10:12 AM
RE: A Philco 38-690 Restoration - by morzh - 05-26-2018, 10:35 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 05:54 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 05:58 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 06:01 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 06:08 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 06:20 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 06:58 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-26-2018, 09:37 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-27-2018, 10:17 PM
RE: A Philco 38-690 Restoration - by Arran - 05-28-2018, 05:04 AM
RE: A Philco 38-690 Restoration - by WyTex - 05-28-2018, 07:03 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-28-2018, 08:03 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-28-2018, 08:15 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-28-2018, 05:59 PM
RE: A Philco 38-690 Restoration - by KCMike - 05-28-2018, 07:36 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-28-2018, 09:21 PM
RE: A Philco 38-690 Restoration - by Arran - 05-29-2018, 03:32 AM
RE: A Philco 38-690 Restoration - by Brad Winder - 05-30-2018, 10:28 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-30-2018, 09:08 PM
RE: A Philco 38-690 Restoration - by tbone - 05-31-2018, 07:46 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-31-2018, 10:43 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 05-31-2018, 10:37 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 06-01-2018, 11:11 PM
RE: A Philco 38-690 Restoration - by Arran - 06-02-2018, 02:35 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 06-02-2018, 07:47 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 06-02-2018, 09:54 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 06-02-2018, 10:16 AM
RE: A Philco 38-690 Restoration - by mikethedruid - 06-02-2018, 12:46 PM
RE: A Philco 38-690 Restoration - by WyTex - 06-02-2018, 01:24 PM
RE: A Philco 38-690 Restoration - by Ed Locker - 06-02-2018, 07:25 PM
RE: A Philco 38-690 Restoration - by Kenradio - 06-02-2018, 07:46 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 06-02-2018, 11:21 PM
RE: A Philco 38-690 Restoration - by EdHolland - 06-03-2018, 10:39 AM
RE: A Philco 38-690 Restoration - by morzh - 06-03-2018, 11:20 AM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 06-03-2018, 11:57 AM
RE: A Philco 38-690 Restoration - by sam - 06-03-2018, 02:07 PM
RE: A Philco 38-690 Restoration - by Ron Ramirez - 06-03-2018, 02:22 PM
RE: A Philco 38-690 Restoration - by tbone - 06-03-2018, 09:04 PM



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