Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

Philco 70 restoration attempt - singing now.
#10

Sometimes the direction of winding does matter in an antenna or RF interstage coil. In these instances there is a combination of capacitive and inductive coupling between the primary and secondary windings.

This is done to increase signal transfer at the high end of the band where the freq response tends to roll off. Sometimes there is an actual coupling cap, other times there is a few extra turns of unterminated winding connected to the primary in close proximity to the secondary. If the winding is done in the wrong direction, the capacitive coupling will be out of phase with the inductive component, resulting in reduced gain at the high end of the tuning range.

So in general, it is always better to note the direction of winding when removing the old coil and rewind in the same direction.


Messages In This Thread
RE: Philco 70 restoration attempt. - by morzh - 01-24-2014, 10:53 PM
RE: Philco 70 restoration attempt. - by morzh - 01-25-2014, 12:00 AM
RE: Philco 70 restoration attempt. - by morzh - 01-25-2014, 12:59 AM
RE: Philco 70 restoration attempt. - by Jamesm - 01-25-2014, 11:57 AM
RE: Philco 70 restoration attempt. - by gregb - 01-25-2014, 03:50 PM
RE: Philco 70 restoration attempt. - by morzh - 01-25-2014, 07:28 PM
RE: Philco 70 restoration attempt. - by morzh - 01-25-2014, 09:13 PM
RE: Philco 70 restoration attempt. - by Mondial - 01-26-2014, 12:28 AM
RE: Philco 70 restoration attempt. - by gregb - 01-26-2014, 12:40 AM
RE: Philco 70 restoration attempt. - by morzh - 01-26-2014, 02:57 PM
RE: Philco 70 restoration attempt. - by Raleigh - 01-27-2014, 02:12 PM
RE: Philco 70 restoration attempt. - by morzh - 01-27-2014, 02:46 PM
RE: Philco 70 restoration attempt. - by morzh - 01-31-2014, 10:10 PM
RE: Philco 70 restoration attempt. - by morzh - 01-31-2014, 10:11 PM
RE: Philco 70 restoration attempt. - by TV MAN - 02-01-2014, 01:20 PM
RE: Philco 70 restoration attempt. - by morzh - 02-01-2014, 01:53 PM
RE: Philco 70 restoration attempt. - by morzh - 02-01-2014, 11:27 PM
RE: Philco 70 restoration attempt. - by morzh - 02-01-2014, 11:39 PM
RE: Philco 70 restoration attempt. - by morzh - 02-02-2014, 09:12 PM
RE: Philco 70 restoration attempt. - by morzh - 02-02-2014, 09:25 PM
RE: Philco 70 restoration attempt. - by morzh - 02-03-2014, 09:32 PM
RE: Philco 70 restoration attempt. - by morzh - 02-05-2014, 01:04 PM
RE: Philco 70 restoration attempt. - by morzh - 02-06-2014, 09:03 PM
RE: Philco 70 restoration attempt. - by morzh - 02-07-2014, 04:52 PM
RE: Philco 70 restoration attempt. - by murf - 02-08-2014, 03:15 PM
RE: Philco 70 restoration attempt. - by morzh - 02-08-2014, 03:41 PM
RE: Philco 70 restoration attempt. - by TV MAN - 02-08-2014, 03:41 PM
RE: Philco 70 restoration attempt. - by morzh - 02-08-2014, 03:49 PM
RE: Philco 70 restoration attempt. - by morzh - 02-10-2014, 10:37 PM
RE: Philco 70 restoration attempt. - by TV MAN - 02-11-2014, 12:16 PM
RE: Philco 70 restoration attempt. - by morzh - 02-11-2014, 12:27 PM
RE: Philco 70 restoration attempt. - by morzh - 02-13-2014, 09:48 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
under chassis parts locator diagram for 1938 Zenith 9s262
Has anyone gone to the trouble of creating an under chassis parts locator image?  Yes, I can identify components by foll...bobloney — 08:57 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Try looking at this site the book mark is for a old generator that I was given. David    https://radionerds.com/index.ph...David — 08:36 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Hello Everyone, I am looking for voltage identification for all the pin positions on the socket of a CRV-20130 power su...Tonym4704 — 08:16 PM
Philco P45-6365 Universal Transformer Instruction Manual
Can anyone guide me to where this may be found?GRG — 03:00 PM
54C Complete Teardown/Rebuild
I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM
HiFi (Chifi) tube amp build - but my own design.
It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM
Philco 71 Code 125
Hello,  I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM
Stromberg Carlson 1500 Squeal
And life just keeps getting more complicated.dconant — 07:57 AM
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM

[-]
Who's Online
There are currently 1975 online users. [Complete List]
» 1 Member(s) | 1974 Guest(s)
Avatar

>