[endrikat]

Hello everyone. I'm new to the forum, but excited by the fact that I picked up this 1963 Gibson Skylark GA-5T for next to nothing and it is in IMMACULATE condition!

I'd like to start using it, but before I do I need to do a few things that I was hoping some of you "veterans" of the forum could help me with. First off, I need to replace the 2-prong power cord with a grounded 3-prong. I don't know how to do this, but have read on other forums that it sometime involves removing a "death-cap", which I would need help in identifying.

Secondly, there is a slight problem with the tremolo. Once it's on, it won't switch back off until you've unplugged the amp and let it sit for a while. Then if you power it back up with the tremolo off, it's fine (until you turn it on again). Any ideas what is causing this?

And lastly, any of you component junkies able to tell if the caps and internals need to be replaced? Things look pretty clean and good to me, but I don't know what I'm looking for. I do know that the seller said the amp was turned on about 10 times total before being put into his closet to store for the next 40+ years.

Thanks!

[Grog]

Congrats! That amp is in "MINT" condition & all original. On an amp like that, that has made it almost 50 years without being molested, I hate to change anything that doesn't need to be changed to make it functional. If the amp has a hum, (that is not from a bad filter cap), just turn the ac plug 180 degrees & the hum should go away. I have a GA-5 & GA-5T from the '65-'67 era, fun little amps! Does yours have a RCA jack on the inside chassis for an optional footswitch?

[endrikat]

 Grog, on 05 February 2012 - 10:08 PM, said:

Congrats! That amp is in "MINT" condition & all original. On an amp like that, that has made it almost 50 years without being molested, I hate to change anything that doesn't need to be changed to make it functional. If the amp has a hum, (that is not from a bad filter cap), just turn the ac plug 180 degrees & the hum should go away. I have a GA-5 & GA-5T from the '65-'67 era, fun little amps! Does yours have a RCA jack on the inside chassis for an optional footswitch?

I didn't see a RCA jack anywhere. So, are you saying that I should be fine with a 2-prong power cord and shouldn't worry about getting shocked? As of right now, with the original components, the amp is quiet (no buzz or hum) and sounds great. The only thing that isn't working correctly is the tremolo (that I mentioned above). I don't know if that is because of a bad cap, a bad tube, or what?

I've just read that electrolytic capacitors need to be replaced after about 15-20 years from so many different sources I figured it was a no-brainer. It seems that you're telling me not to do anything to the amp!?

[Grog]

 endrikat, on 06 February 2012 - 09:39 AM, said:

I didn't see a RCA jack anywhere. So, are you saying that I should be fine with a 2-prong power cord and shouldn't worry about getting shocked? As of right now, with the original components, the amp is quiet (no buzz or hum) and sounds great. The only thing that isn't working correctly is the tremolo (that I mentioned above). I don't know if that is because of a bad cap, a bad tube, or what?

I've just read that electrolytic capacitors need to be replaced after about 15-20 years from so many different sources I figured it was a no-brainer. It seems that you're telling me not to do anything to the amp!?

If it were mine, I wouldn't change a thing, since you don't have any hum at this time. It is true that most filter caps don't last as long as yours has, but unless you plan on using it as your main stage amp and reliability is important, it's working fine now. The tremolo is hopefully an easy fix, maybe a tube or spray the frequency pot with tuner cleaner. Schematics are readily available online. Most of the Crestliner amp series are prone to corosion on the amp chassis, yours is spotless! That brown capacitor, with the #2 on it is the death cap. Caps like that are hard to come by, modern replacements work fine, you just have to mount them in such a way that doesn't allow anything to short out against the chassis.

[Grog]

I went through a bunch of old photos & found a few of changing the filter caps on my GA-5T Skylark.......... Mine is the model that came out right after yours.

[Cam in alberta]

Put a grounded plug end on it. It is simple and may save your life. Beautiful amp by the way. Thought my Ga-8T was mint but that one is almost beyound mint.

[ampKing]

I have one of the GA-5T amps too. I like the tone of it (as compared to a Fend deluxe reverb.)
Years ago, I replaced the dual ganged filter cap ( brown with 2 red wires attached) with a metal one by Sprague. I just took the mounting bracket out of the old position, positioned it around the new cap and used hot melt glue ( or epoxy) to
hold the new cap in a new position - in front of the transformer. I have a black wire, that connects the ground of the can to the chassis ground. The cap is marked: 8 - 20 MFD, 8 - 20 MFD at 450 V. This just means there are two rather
big capacitors, 10 to 20 MFD, smoothing out the ripple on the power supply. The can cap could be replaced with two indivual caps, but since your amp is so minty, I'd attempt to keep it original. This might mean putting the cap back in its original
position, that is up to you. Please keep in mind that the "dressing" of the point to point wiring was done carefully, and with noise reduction in mind, so every little bend of the connection wires may have a purpose. However, on the filter caps, this should not really be an issue; just don't move the red filter cap wires next to the signal wires connecting the tubes! The caps are a little hard to find, but you can get one here: http://tubedepot.com/can.html
CP-CE-20X2-450V ( one of the antique radio repair companies actually makes these caps.)
I don't think of it as a death cap. And I still have a 2 prong plug on my amp. Whatever, do not stand in water, while playing the guitar! { maybe a ground cord IS good - not trying to argue that point...) If you or I DID connect a grounded cord, then you need to be careful to get the polarity of the AC wires correct, because it will usually hum if the hot and neutral wires are reversed. You could check with an AC volt meter, to make sure there is no voltage potential between the chassis, and your house ground... if you are going out and gigging with the amp, then, perhaps, a grounded cord would be a good idea.
I'll have to research a little, to figure out why the tremelo gets stuck...
Regards,

JAM

[ampKing]

Here is another source for the filter capacitor:
http://www.amplified...s/C-EC20-20-450

Cheers!

[vexorgtr]

I had one of those re-done awhile back. Basically, you just need to have the "Big Paper" power caps replaced. 3 Prong cord isn't a bad idea either.

Before: my amp gave free shocks, trem made weird buzzing sounds, Amp was noisy
After: Amp is Quiet, No Shocks, no trem works well.

[mgreene300]

Mine is a little different than yours. Is the death cap the black sprague to the left of the filter cap in your pic? Looks like it goes from the ON/OFF to the power transformer?

[The Green Hornet]

I have a 1962 Gibson Skylark GA5T in mint condition too. The woman I bought it from said it was her mothers and passed it down to her. Was used for Lap Steel. I replaced the caps and cleaned all the controls. Also had the tech to put on the 3 prong cord. Sounds amazing and way warmer than my 68 Vibro Champ.

[MarkR1]

I've got a 59 GA-18T Explorer and a 59 GA-8 Gibsonette and both came with the original 2 prong plug. The GA-18T I immediately took it to my amp tech and had the cord changed to a grounded cord. The GA-8 I got it a couple of months ago and waited to have the plug changed. I was playing it one day and was touching the strings of my guitar and went to turn it off and it gave me a buzz that I won't forget for a while. Needless to say it was in the shop the next day getting its plug changed too. I would defintely recommend switching to a grounded plug. I told them I wanted to keep the original cord tho which I keep in the bottom of the amp.