Weird video in/out connectors on 3V22 - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Station X · 20th May 2010, 7:04 pm

I have the same flux and 60/40 solder too, but it just doesn't work on some connectors. The solder just won't adhere to the surface. you have to file it down to the brass underneath.

camtechman · 20th May 2010, 7:35 pm

Graham,

I have the same problem with 3.5mm mono & 3.5mm stereo jack plugs and sometimes even a moderate heat soldering iron and being as quick as possible causes the white (nylon) spacers on the back of the plug assembly to melt and thereby loosening the centre contact/s.

a_strong · 20th May 2010, 7:54 pm

BNC/TNC and "N" type preserve their design impedance to much higher frequencies than the PL259/SO239 badly named "UHF" connectors whose performance is beginning to deteriorate above a few tens of MHz. The N and BNC/TNC also have better weather proofing characteristics than the PL259.

A note for the unwary, BNC and N come in 50 and 75 ohm impedance and the pin of a 50 ohm plug is fatter than the pin of a 75 ohm plug. Whilst a 75 ohm plug will fit into a 50 ohms socket it can give rise to unreliable connections but not permanently damage the socket. A 50 ohm plug into a 75 ohm socket can damage the socket by opening up the centre connection so it is unwise to try to cross breed them

Alan

Kat Manton · 20th May 2010, 8:00 pm

Hi,

Drifting further OT, but still relevant; IME many connectors can be fitted more easily, without damage, if they're plugged into a socket first.

This helps dissipate heat from where it isn't wanted and helps hold pins in place should anything melt. I do this as a matter of course with DIN, phono, 3.5mm jacks, some types of 'Belling Lee' co-ax plugs; anything where there's a chance that pins may wander out of alignment if the insulation goes soft.

It also helps to solder quickly with a hot, temperature-controlled iron of adequate power. A 45W Weller 'TCP' with a No.8 bit (800ºF) can get the tags in a connector up to solder-melting temperature much more rapidly than a 15W Antex; heat then doesn't have much time to spread to places where you don't want it.

Cheers, Kat

repairman 1234 · 20th May 2010, 10:30 pm

Hi,
Yep, Not an unusual one to me either, Pl 259's. I have this adaptor that changes it to BNC in a very fetching Gold...well, gold plated anyway

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P.S. These were often found in pairs in the old VCR copy lead kits which are still available from those cheap shops....(B&M i think) only a couple of quid for the whole set!

20th May 2010, 7:04 pm	#21
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: Weird video in/out connectors on 3V22 I have the same flux and 60/40 solder too, but it just doesn't work on some connectors. The solder just won't adhere to the surface. you have to file it down to the brass underneath. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

20th May 2010, 7:35 pm	#22
camtechman Nonode Join Date: Jan 2008 Location: Milton Keynes, Bucks. UK. Posts: 2,552	Re: Weird video in/out connectors on 3V22 Graham, I have the same problem with 3.5mm mono & 3.5mm stereo jack plugs and sometimes even a moderate heat soldering iron and being as quick as possible causes the white (nylon) spacers on the back of the plug assembly to melt and thereby loosening the centre contact/s. __________________ When I die, please don't let my Wife sell my collection for the amount I told her I paid for it!

20th May 2010, 7:54 pm	#23
a_strong Pentode Join Date: Feb 2007 Location: South Yorkshire, UK. Posts: 134	Re: Weird video in/out connectors on 3V22 BNC/TNC and "N" type preserve their design impedance to much higher frequencies than the PL259/SO239 badly named "UHF" connectors whose performance is beginning to deteriorate above a few tens of MHz. The N and BNC/TNC also have better weather proofing characteristics than the PL259. A note for the unwary, BNC and N come in 50 and 75 ohm impedance and the pin of a 50 ohm plug is fatter than the pin of a 75 ohm plug. Whilst a 75 ohm plug will fit into a 50 ohms socket it can give rise to unreliable connections but not permanently damage the socket. A 50 ohm plug into a 75 ohm socket can damage the socket by opening up the centre connection so it is unwise to try to cross breed them Alan

20th May 2010, 8:00 pm	#24
Kat Manton Retired Dormant Member Join Date: Jul 2005 Location: West Yorkshire, UK. Posts: 1,700	Re: Weird video in/out connectors on 3V22 Hi, Drifting further OT, but still relevant; IME many connectors can be fitted more easily, without damage, if they're plugged into a socket first. This helps dissipate heat from where it isn't wanted and helps hold pins in place should anything melt. I do this as a matter of course with DIN, phono, 3.5mm jacks, some types of 'Belling Lee' co-ax plugs; anything where there's a chance that pins may wander out of alignment if the insulation goes soft. It also helps to solder quickly with a hot, temperature-controlled iron of adequate power. A 45W Weller 'TCP' with a No.8 bit (800ºF) can get the tags in a connector up to solder-melting temperature much more rapidly than a 15W Antex; heat then doesn't have much time to spread to places where you don't want it. Cheers, Kat

20th May 2010, 10:30 pm	#25
repairman 1234 Retired Dormant Member Join Date: Sep 2007 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 749	Re: Weird video in/out connectors on 3V22 Hi, Yep, Not an unusual one to me either, Pl 259's. I have this adaptor that changes it to BNC in a very fetching Gold...well, gold plated anyway P.S. These were often found in pairs in the old VCR copy lead kits which are still available from those cheap shops....(B&M i think) only a couple of quid for the whole set!