What did I break? Splawn content

[Exodus5]

A few weeks ago I bought a Splawn super sport head. It sounds good, but the tubes were original and The amp is about five years old, so it was time for them to be changed. I bought a new set of 6v6 tubes and put them in with my tube biasing rig but noticed putting my biasing rig into one of the sockets was much harder than the other. That tube did not light up nearly as bright as the other and showed 0 mV on the tester while the other was close to the correct bias setting.
I put the original tube back in but it's the same situation so obviously I broke something loose on one of the sockets. It's pretty tight in there but my checking didn't find an obvious issue. I know you guys know a lot about what each lead on the socket does so I'm hoping that someone can narrow down which leg of the socket I need to be looking at ....

[tedmich]

no schematics for these heads but the tube is pretty predictable.
Can't think what you did by "forcing it w/out lube" but maybe check heaters and then (carefully!) B+
Does your "bias rig" read plate voltages or just bias current through 1 ohm resistor?
Any fuses out?

[Exodus5]

All fuses are good.
I think I smell magic electronic smoke, but nothing appears burnt.
Due to the placement of the boards around it I cannot get the plate voltage (my biasing rig only shows mV for biasing) but I verified the plate resistors are the same rating, so apparently the resistor isn't open.

[Exodus5]

no schematics for these heads but the tube is pretty predictable.
Can't think what you did by "forcing it w/out lube" but maybe check heaters and then (carefully!) B+
Does your "bias rig" read plate voltages or just bias current through 1 ohm resistor?
Any fuses out?

I think I've located the problem there is a square resistor "XICON P 5W 1K J" that connects leg four to leg six. That reads open.

[Chuck H]

Nothing about that resistor should cause the socket to be tight. You should correct the amp for both electronic and physical problems because we can't know if that resistor (the screen resistor) failed with the old tubes or as a result of what you may have broken when forcing the socket. A typical novice mistake is to locate a bad component and simply replace it. That doesn't address any problem that may have caused the failure and a new failure is a common result. Pull the tubes and check that troubled socket for shorts, damage, bent pin clips, etc.

Can we assume that all the bias test plugs and tubes in question DO still have their center key for proper alignment?

[Exodus5]

Nothing about that resistor should cause the socket to be tight. You should correct the amp for both electronic and physical problems because we can't know if that resistor (the screen resistor) failed with the old tubes or as a result of what you may have broken when forcing the socket. A typical novice mistake is to locate a bad component and simply replace it. That doesn't address any problem that may have caused the failure and a new failure is a common result. Pull the tubes and check that troubled socket for shorts, damage, bent pin clips, etc.

Can we assume that all the bias test plugs and tubes in question DO still have their center key for proper alignment?

I have taken he amp to a tech. I do know the key on the tubes and bias probes were all good, but you are right in that I probably caused some other issue with wiggling the tube out.

[Leo_Gnardo]

tubes in question DO still have their center key for proper alignment?

I do know the key on the tubes and bias probes were all good

I bought a new set of 6v6 tubes and put them in with my tube biasing rig but noticed putting my biasing rig into one of the sockets was much harder than the other.

On some octal sockets it's possible to force the tube into the socket despite incorrect alignment of the key. That would also make for what feels to be a very tight fit. It's possible to toast that 1K resistor if the tube isn't correctly inserted. Eight ways to do it, only one of them is right. Gotta look at what you're doing, with good lighting and without distractions, make sure it's right.

[Chuck H]

I haven't experienced that! So, yeah, that could be a problem.