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BT22
Posted on Wednesday, August 07, 2002 - 3:02 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Just picked up a real nice big base amplifier and was wondering if anyone knew anything about it. It is called a T-600. It is all black and looks almost identical to a Phantom 500 - has 10 tubes and 3 power supplys all located in the same area as they are on a Phantom. Is this a high drive amp? The guy I got it from ran a Golden Falcon into it?? Also what is the grid tune for? Do I tune the first amp and then it? And finally, when we tested it out last night - when it hit close to 1100 watts I lost a bunch of lights and power in my house. I replaced fuses but can't get the light to come back on. The fuses are those old cylinder looking ones. My house was built in the late 40's. Will I need to rewire that particular outlet? Any help would be great!! Thanx in advance!

BT
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Spiderleggs
Posted on Wednesday, August 07, 2002 - 11:48 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The T-600 was made by D&A also. It was a higher output version of the phantom. However it is a low drive amp, unless the drivers were redone so that you had 10 finals, and needed a higher signal to drive them. It has been a few years, have forgotten what all the knobs were for.
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2600
Posted on Wednesday, August 07, 2002 - 11:08 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If the house was wired in the 40's this thing is just too big. Unless you stick to low side, it will draw MORE than 15 amps. In the 40's 15 amps was the biggest 120 circuit that was legal to install. Nowadays, it's legal to run #12 wire to a 120 circuit and use a 20 Amp breaker on it. A 20 Amp-rated circuit will run it, if nothing else much is drawing power with the amp on that breaker (uh, fuse?).
You can run it on low side, assuming low side works. This will reduce the current draw on your outlet, along with the power it delivers.
The grid tune, if it is still hooked up, is a little funny. Usually, setting it for best swing will work okay. If the radio has a SWR meter, see what it reads WITH THE AMP KEYED. This way, the internal radio SWR meter won't be reading the antenna any more, it will be reading the drive circuit in the amp. If you see a reading on the radio's internal SWR meter higher than 2 to 1, try turning the grid tune JUST A LITTLE to one side or the other from where you peaked it. In one of the two directions, the SWR reading will start to fall. Usually, you can get it below 2 to 1 without sacrificing more than 10% of your swing. If this model is old enough to use a skinny little keying tube in the very back, near the Grid Tune control, turning the control too far may cause the relay to chatter. Just turn it back to where the relay stays keyed. Usually the setting that gives you best peak output will keep the relay quiet, also.
73
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BT22
Posted on Saturday, August 17, 2002 - 7:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

for some reason this amp has been set up to be driven with another amplifier. does anyone have the schematic for a newer phantom 500? my repair guy says it has a solid state keying circuit in it unlike the older models. it is very similar to the phantom 500. thanks!
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Northwind
Posted on Friday, August 30, 2002 - 11:41 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Just some further explanation of what BT22 needs to get his amp back to normal. Some one has been in it and modified it for high drive. The receive amplifier has been disconnected. The grid tune circuit has been disconnected. Help is needed to put this unit back to original. Of course it is a phantom 500. A schematic is what he really needs. Does anyone have a lead on one for him? Thanks in advance.
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2600
Posted on Monday, September 02, 2002 - 2:04 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Wellllll, the ONLY printed schematic I have ever been able to get for the Phantom is the original 12-tube version that has THREE relays and a keying tube. I have NEVER seen a printed diagram for any later version. Later D&A amplifiers had the skinny little keying tube in the back, but only two relays (better). Even later versions used 12-volt relays with a transistor to key them. I have YET to see a printed schematic for one of those. Ever.

This really narrows the field of who you can get to work on it down to folks who don't NEED a diagram. Sad, but true.
73