I am working on a majestic model 70 radio i need some advice on the problem i am trying to solve.
Basically i have no sound or static coming from the speaker.
In the rf amp section it uses a simple 26 triode tube with direct heat.
My plate voltages are correct or near anyway the 26's plate voltage needs to be 96 and it is 105.
heater voltage is 1.4 volts
all the other plate voltages have been checked and are very close to spec.

I signal injected a modulated am signal into the antenna terminals. I can tune in the frequency to the first gird
my scope shows a signal of about 500mv pp. no dc component. on the plate i am seeing a very small signal below the ac noise coming from the power supply. The grid of the second 26 has no dc bias component but the signal is for the most part missing. ( you can see a very very small rf signal)
(also all tubes have been tested and found to be good)
The coupling from the first rf to the second is by transformer.

questions.
1. when i checked the plate of the first rf could the scope probe load down the output giving me a false reading?
2. if i am having a tuning problem the secondary of the transformer has another tuning section if the secondary of the transformer's tuning is rejecting my target frequency can i see that reflected in the plate of the first tube? - believe there should be enough isolation between the two sections that if i had a tuning issue at the second rf amp stage it would not affect the plate on the first stage.

3. Please any ideas at all i am stuck on this one

wanted to add one more thing the .5 uf cap on the plate b+ is fine so the rf signal should have a good return. So i don't think that could be the issue. I am still baffled. I should have a substantial rf signal off of that plate of the first rf amp. even if i am having issues with the tuning capacitor on the second rf stage.

That set pretty simple, which leaves very few possibilities for problems. Have you checked the secondaries of the RF coils? They could well be open, as much as the primaries. do on them, Theig bugaboo on these sets is the die cast anchor of the rotor plates. They expand and short. If you are plagued by that problem, you can sometimes go down to the shaft of the condenser rotor and bend the plates apart.

T

yes the tuning cap was shorted i did bend them but it was a job to get it back. they don't short now when engaged in any position. Just to make sure i used a pretty high test freq around 1250 khz the rotor plates were mostly out so i know that the tuning cap is not responsible, but i am worried about the capacitance change that may have occurred.

The primary's can't be open because i have my plate voltage on all tubes, but the secondaries - did not check i will do that.

But shouldn't i have seen a significant signal on the plate? - the signal on the plate was below the noise level my noise level is about .20 mv

When i touch my meter to the plate i do get a pop in the speakers. i don't know if that is from amplification of the probe current draw or if it was just transmitted through the plate voltage to the output tubes.

ok, i checked all the transformers and no opens, i also tried to ring the coils but open air core does not ring well and shows short or zero rings. I don’t think they are shorted just my ringer will not work with open air core very well.
I am still stumped on this one. i have a good ground to the transformers secondary.
the only thing i am left with is possibly the tuner plates after getting them not to short i may have messed up the capacitance range ????

Any other ideas. I am still confronted with the small output signal on the plate of the first tube after i swamped a signal in with an rf generator. I thought i could just push the signal through just to see if i could get any signal through but still no joy. It is mostly gone on the second rf amp grid.