Broken input jack on Amp

[tsmilliner]

Hi folks,
I was playing tonight, and the cord got snagged on something and broke the nut off of the input jack (cheap plastic crap) on my RM4 Pre-Amp. It still works okay, I have to slip the nut around the plug on the cord to keep it from going into too far.

I haven't opened the unit up yet, but was curious, does anyone know if a regular 1/4 switch craft jack will work, or are these proprietary to the particular amplifier.


It is a Randall RM 4 Preamp.

Thnks Tom

[Enzo]

Cheap plastic crap because it broke? When you step on a cord, it can break a jack if it is plastic, yes. Or if it is metal, you can bend your panel all up. Possibly break the circuit board inside.

Often too plastic jacks are plastic because they want them insulated from the panel. if you replace that with a metal one you may add a bunch of hum, since it would alter the grounding scheme.

This jack wouldn;t be proprietary, some jack company made it. Chances are we can come up with it, might be very common type even, but you could install any jack you can fit in the space. Mount it upside down and run short wires to the circuit board if necessary. I prefer to replace jacks with the same type as the original.

[tsmilliner]

Yes, Cheap plastic crap! Because I didn't clear my cord properly, and I am a clumbsy oaf and I stepped on it and I am frustrated and pissed at myself for not being more careful! So who else can I blame but the amp company?? LOL

Thanks for the insight on the insulating properties. It did not occur to me that this might have been a part of a well designed plan to keep the noise down.

I actually have found a few plastic fender jacks online since posting that look like they will fit, I will probably go that way and keep it as designed.

Only question is how many pins 9 or 4, I will crack it open tomorrow and look.

Should be easy enough.

Thanks, Tom

[Gtr_tech]

You can use a heavier jack as long as you use nylon insulating shoulder washers, but that will depend on the size of the panel hole. You may need to enlarge it some. I do this quite often. I just don't care for those "cliff" style jacks....once I put in a metal bushing Switchcraft or similar it usually solves that problem for good. Keep in mind you need to fly leads from the pcb to the jack.

[Bruce / Mission Amps]

Actually, I agree with your first assessment... those PCB mounted plastic jacks as found in modern Fender amps are cheap, junky, total pieces of crap.
I've replaced more of those turds on more amps then any other jack in any amps since 1986.

[Enzo]

Oh I am no fan of those clear top things, but i don;t like blanket statements so much either.

[Bruce / Mission Amps]

Oh I am no fan of those clear top things, but i don;t like blanket statements so much either.

Yup, that is exactly the jack I'm talking about too....

[Mars Amp Repair]

Yeah,
I agree that any type of jack is unlikely to survive a 'trip' on the cord without some kind of damage done.

I have found that even the generic Fender jacks from CE distributing for about 1/2 the price of the Fender's are even a better jack, albeit still cheesmo for the few threads they leave for the nut to grab onto.

On the HR Deluxe & Deville's I have taken in some cases where the customer has requested better jacks to using the 6 legged with metal insert ones that Line 6 uses for their input jacks. They are pretty tough & make great contact to the 1/4" plug as well as the jack switches have height steps in them so that they actually remain strongly tensioned from tip to ring.

You do have to run wires to them from the jacks to the pcb, but it actually ends up only using only 3 wires when all is said & done. The bulk of the wiring is between the jacks & not on the board...

glen

[johnthe cat]

Hi good evening as it is here in sunny spain, can you give me any more info on ce distributing so i can contact them for one of these jacks i have just got myself a fender 85 but it has a broken jack, i cant locate one here in spain, regards john

[52 Bill]

CE is the commercial company that only deals with wholesale buyers, Antique Electronics is the consumer company.

[pontiacpete]

Antique Electronic Supply LLC