k4900/ what causes neck board sockets to go bad?

cleverlyj

Well-known member

Donor 2011
Joined
Aug 6, 2003
Messages
14,653
Reaction score
513
Location
Northglenn, Colorado
so i've got a 4900 that lost green. resoldered every spot on the neck board and it didn't change. noticed when i unintentionally bumped the neck board that various colors came and went. turns out the pin sockets on the neck board appear to be worn out, as gently moving the neck board causes the colors to come back.

i have another neck board off a junker 4900 chassis that i swapped in and it appears to have fixed the issue.

so, how often do sockets go bad like that, and is there anything that can be fixed in the socket?

also, does anyone do neckboard swaps? i searched for it on the forum and couldn't find anything. the part numbers for both boards match so i'm sure i'm fine, just surprised i couldn't find any prior info on it.
 
I swapped a neckboard on a 4900 that had different "numbers" on it than the original I had.

I was worried and took a chance, but it worked just fine.

I do remember swapping a cap on the neckboard I received. There was just ONE in a different position. So I just moved it.

After a year and half (thanks again Cliffo) it still works just fine.

Funny, I just paid Cliffo this morning for shipping me the neckboard for the 4900....a year and a half late.:(
 
I do remember swapping a cap on the neckboard I received. There was just ONE in a different position. So I just moved it.

yeah, i think it's a tantalum cap that's at c404 on one and c414 on the other, or something like that. i had the same thing, and i said fuck it, part number's the same.
 
The pins inside the socket are probably tarnished. I unsolder the socket completely and remove it from the board. Then I take it to the sink and spray it out with Mean Green (or other similar household spray cleaners), rinse with hot water, and blow dry with a hair dryer. Socket is usually good to go again.
 
I've had a couple G-07's, WG7000, and a WG6100 with this same issue....some of mine also had focus issues. I've seen this, probably, 10 times over the years. I always take a small flat blade screw drives and crack open the bad neck socket....just to see what's up. Every time.......the pins inside are caked with rust/corrosion. All the componets on the chassis's look fine. My thoughts.....people ran these chassis through their dishwashers (which is growing in popularity amongst collectors), or hosed them off to clean them. After the bath, the chassis were never thoroughly dried......thus, oxidation set in. I'd love to find a place that sells new neck sockets (CR23 type/size).

Edward
 
Back
Top Bottom