posted 01 March 2005 09:40 AM
I would disassemble the amp and perform a routine maintenence to it. I bet that this hasn't been done in a while. All amps need this from time to time.
Make sure your amp is unplugged from the AC source (wall outlet) and that you discharge the filter caps first thing before doing anything else so your amp is safe to work on.
Here's an old post I wrote, on point, for NV 400 maintenence for this forum:
All amps have their particular failure mechanisms. With the NV 400, it is the switched jacks and the Molex connectors. These are the weak links in most Peavey amps I've seen and worked on. All amps need routine maintenence (just like tires, belts, wipers on your car).
The metal Switchcraft switched jacks can be cleaned and renewed indefinitely. The plastic jacks should be removed from the amp and professionally cleaned and, occasionally, replaced. They are not, unfortunately, in the Switchcraft league. There are seven jacks in the NV 400 and all need occasional service. The two front panel Input jacks, the front panel Patch In jack and the rear panel Power Amp In jack are the switched jacks and need special attention. The others need less maintenence than the switched jacks. As it has been pointed out, it's the switches within the jacks that carry signal and fail/become intermittent.
Also, Molex connectors have shown themselves to be a weak link and these should be carefully re-tensioned and cleaned. Pay special attention to the Molex connector that goes to the reverb tank in the bottom of the amp. Use a cleaner spray and gently re-tension the sleeves that connect to the pins on the amp's circuitboard. Mark the connector before removing it so it goes back on the exact same pins when reseating it. Peavey solder joints, over the years, have proven to be completely adequate for the job but like all amps, an occasional solder joint fails or becomes intermittent.
From a tech standpoint, intermittent problems are the most frustrating and I can relate the the posts I've read here but with simple routine maintenence the NV 400 can be a very, very reliable amp and about the best value-for-money in the steel guitar universe. There is no reason that all of your NV 400 amps wouldn't last well into this century with proper maintenence.
Sometimes, spraying into the jack from outside the amp will work and sometimes it won't. Most folks aren't qualified to go 'under the hood' and I've seen many a time more harm than good accomplished from 'user servicing'.
Using a short patch cord, on the rear panel from Preamp Out to Power Amp In, to get you thru a few gigs might work but it's not really attacking the problem at its root. Peavey parts are priced exceptionally reasonably and I'd recommend all those patch cord folks get some new plastic jacks, or better yet Switchcraft metal jacks, installed. And, please establish a rapport with your local (and competent) amp tech. That's the real solution!