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[K3NRX]

….is not real tight on the anode of an amps tube?….could that result in a breakdown and/or loss of transmission?……a clamp is not griping the top part of the tube very well, and I have been seeing the transmit quit sending the swr into infinite bonkers….could that be the cause of this transmission shutdown that I’m experiencing?….

V
K3NRX

[W9WQA]

clamp or plate cap loose???
if its just the clamp, id tighten it.

[K3NRX]

clamp or plate cap loose???
if its just the clamp, id tighten it.

It’s a tiny metal clamp that is supposed to securely grip the top of the tube. I tried tightening it…or squeezing it inward a bit but the grip on the tube is still not tight….what I really want to know is why my transmit drops, or sometimes doesn’t work at all….there is drain from the rigs power supply, but keying down, nothing out and SWR is crazy out of control….could this insecure tube clamp be what’s causing this?

V
K3NRX

[K3NRX]

To expand a bit, the tubes are 6LQ6 Sweep Tubes and the Amp is an Ameritron AL-84....the relay clicks fine, and all wires to coming in and out of the amp are rock solid as far as solder connections go.....

[K8AXW]

….what I really want to know is why my transmit drops, or sometimes doesn’t work at all….there is drain from the rigs power supply, but keying down, nothing out and SWR is crazy out of control….could this insecure tube clamp be what’s causing this?

NRX:  Could you expand on these points a bit?  How much "drain" are you getting from the amps power supply?  What does SWR crazy out of control mean? Can you operate into a dummy load?  Can you supply meter readings?

[AA7IS]

To expand a bit, the tubes are 6LQ6 Sweep Tubes and the Amp is an Ameritron AL-84....the relay clicks fine, and all wires to coming in and out of the amp are rock solid as far as solder connections go.....

It's very unlikely your problem is the "clamp" being tight enough.
That point is  very high impedance and takes very little contact to be ok.
It's far more likely a relay contact.

[AE0Q]

a clamp is not griping the top part of the tube very well, and I have been seeing the transmit quit sending the swr into infinite bonkers….

Is this the SWR 'seen' by the radio driving the amp (the Input SWR)?

In a tetrode amp that is grid driven, the amp typically has a 50 ohm load in it for the radio load, so lack of HV doesn't make the input SWR change.

In a triode grounded-grid amp, the tube circuit is part of the load for the radio, so if the tube loses the HV that could cause the radio to see a high SWR.

Glenn AE0Q

[K3NRX]

Is this the SWR 'seen' by the radio driving the amp (the Input SWR)? -- Answer: Yes...the swr meter on the rig is what's going infinite swr.....the SWR/power meter on the outboard tuner is just dead.....with regard to the clamp on the top of the tube, I managed to get it a bit more snug for what it's worth.....I sprayed the contacts on the relay and on the coax ports on the back of the rig......but I have not yet reassembled the station.....hope this works....if not, I think that relay is going to have to go, or at the very least, need reconnected.....

V
K3NRX

[K8AXW]

One other thing, a loose clamp on ONE of the sweep tubes wouldn't create the problem(s) you're experiencing.

[AE0Q]

Is this the SWR 'seen' by the radio driving the amp (the Input SWR)? -- Answer: Yes...the swr meter on the rig is what's going infinite swr..

Since the problem is intermittent, it does sound like that 3-pole T/R relay is bad.