Traynor YBA-1 2-3 prong power cord question. . .

[drasp]

So I'd go with the modern version of the 40 and use the 47uF caps.

I hope 33uF is good enough. I realized that the F&Ts come in either a SINGLE 47uF or a double 33uF. Since I'm trying to replace two 2x40uF caps, it sounds like two 2x33uF caps may be the way to go. . .

LINKAGE < < < Dual 33uF @ Metro

[Dave Curtis, dB AudioTech]

[QUOTE=drasp;97064]Alright, work is done (for tonight).

I wired it as you suggested with one change: instead of the black wire going:



I went:

circuit breaker, switch & left the original split to the transformer & lamp on middle lug of switch, added wire going to lower lug on 120VAC outlet.

Hopefully there isn't some reason I'm missing to have the hot leads for the transformer & lamp moved to the outlet, the upper (white) lug on the outlet is already crowded & I only wanted to move/change runs of wire where necessary. I'd already left the ground wire a bit longer than the hot & neutral + I terminated it in a ring lug at one of the bolts that holds a transformer to the chassis. I'm glad to have retained the 2 prong outlet, it would be handy if I were having trouble finding an outlet for my 1SPOT adapter.

Anyhow, pictures, as promised:

1st, the finished (I think) 3 prong conversion:




Well, having the convenience outlet after the circuit breaker may not be the best... That CB is only for the load of the amp, not the additional load of what may be plugged into the receptacle. Those receptacles should be wired straight off the cord; before any fuses or switches.

[shredhead]

safety 1st

First mod i do to any vintage amp. Polarity switch can then be removed, makes a great spot for master volume.

[drasp]

Believe it or not, I no longer own the YBA-1 in my first post, but just acquired a great '68 YBA-1. It appears to be a bit of an odd ball. 4x digit serial starting w/ 2, everything dates it as a '68. Has a choke, but ss. recitifier + the output tubes are 7027As (both in the amp & on the chart). Must have been a transitional amp. . .

Anyhow - I haven't even powered it on for the first time. Doing the 3-prong conversion & replacing a broken power switch on the front. I realized as I was replacing the switch, there is, what appears to be a 2nd "death cap" @ the front switch - should I lift this as well?

[drasp]

Just for the heck of it, I thought I'd update this w/ before & after pix of my '68 YBA-1's 3-prong conversion. Critique is welcome, of course!





And, here is a picture of the cap -> ground on the standby switch, as mentioned in the post above. . .still unsure if I should leave it or not.

[Dave Curtis, dB AudioTech]

You can leave the one on the standby switch; it's not a "death" cap. It will suppress switching transients. Take a look at the convenience receptacle; they did the same thing that Fender did for years... it's wired backwards. The hot should be wired to the narrow slot (brass screw) and the neutral goes to the wide slot (silver screw).

[garthplinko]

Thank you all very much

Sorry to bump an old thread, especially being new to this forum.

I just wanted to shamelessly gush and thank the original poster of the thread - my YBA-1 is EXACTLY the same as his older late 60s model later in the thread (these are not nearly as easy to get the chassis in/out as the 70's bumper-style). Your pictures and work here are greatly appreciated -thank you so much you've saved me a lot of anxiety and asked all the questions I was going to ask.

I think for mine, I'm going to put in an IEC connector. Not sure. Dunno if it will decrease the value. It's not really a museum piece anyway.

Thanks again SO MUCH for a really great thread!

[pdx]

I am trying to witch out a 2 prong to 3 prong on an Acoustic 150 and there seems to be two "death caps."


any advice?

[shredhead]

I am trying to witch out a 2 prong to 3 prong on an Acoustic 150 and there seems to be two "death caps."


any advice?

Once the new 3 prong plug is installed, the death caps can both be removed. You don't need them anymore. Just make sure you connect the hot and neutral correctly in order to be in phase. The polarity switch is also useless and may be removed .The hole can be used for something else. I've seen guys install a GFCI for even more protection.