Recently I came into possession of a minty 10-tube triple-stage Phantom (tan model) and yes there are problems with it. Specifically:
1) Even with 10 tubes showing over 90% emission I can't seem to get more than 400 watts out of it and on-air reports indicate that I sound a bit off-frequency.(!) Input power is approx 4 w AM. I have followed all recommended tuning procedures as detailed in the original manual from D&A. Additionally, when using an external meter it shows a downward swing.
2) A previous owner did a bit of work on it by replacing the original power level switches with 3 way switches. Depending on the position of the switches it operates on very low (< 100w) medium (around 200 w) or high ( 400 w). In certain positions the relays engage but there is no output at all.
3) The sideband delay sticks for about half a second after unkeying.
4) The preamp when switched ON actually has the opposite effect of REDUCING receiver sensitivity. Not much of an issue since most of the preamps on these old D&A amps never really worked anyway but I've never seen one that makes it worse when it's turned on!
5) When tuning up the meters peg hard all the way to the right.
A close visual inspection of the chassi does not show any obviously failed components. It doesn't smell as if the magic smoke has been let out of anything, nothing looks overly sweated or abused, however I may or may not have heard something go POP during the initial tuning. Again nothing on top or underneath appears damaged but there are some disc caps underneath the tubes that look as if they are bubbling a bit and there are a couple of large disc caps topside that are connected to the tuning coil that don't look quite right.
All I have done to it is replace the tubes, dust off the chassi and replace the 3 prong plug as a previous owner had removed the ground lug.
I'm very limited on test equipment and HV experience but know enough NOT to go poking around inside this thing without taking the proper precautions.
I have numerous photos of the unit and will post them if requested.
1) Even with 10 tubes showing over 90% emission I can't seem to get more than 400 watts out of it and on-air reports indicate that I sound a bit off-frequency.(!) Input power is approx 4 w AM. I have followed all recommended tuning procedures as detailed in the original manual from D&A. Additionally, when using an external meter it shows a downward swing.
2) A previous owner did a bit of work on it by replacing the original power level switches with 3 way switches. Depending on the position of the switches it operates on very low (< 100w) medium (around 200 w) or high ( 400 w). In certain positions the relays engage but there is no output at all.
3) The sideband delay sticks for about half a second after unkeying.
4) The preamp when switched ON actually has the opposite effect of REDUCING receiver sensitivity. Not much of an issue since most of the preamps on these old D&A amps never really worked anyway but I've never seen one that makes it worse when it's turned on!
5) When tuning up the meters peg hard all the way to the right.
A close visual inspection of the chassi does not show any obviously failed components. It doesn't smell as if the magic smoke has been let out of anything, nothing looks overly sweated or abused, however I may or may not have heard something go POP during the initial tuning. Again nothing on top or underneath appears damaged but there are some disc caps underneath the tubes that look as if they are bubbling a bit and there are a couple of large disc caps topside that are connected to the tuning coil that don't look quite right.
All I have done to it is replace the tubes, dust off the chassi and replace the 3 prong plug as a previous owner had removed the ground lug.
I'm very limited on test equipment and HV experience but know enough NOT to go poking around inside this thing without taking the proper precautions.
I have numerous photos of the unit and will post them if requested.
