Midland 7001

[bernado]

Good day!
I own 2 Midland 7001 that do not work! Both have installed the board PTBM059COX and PTOS006AOX and the nameplate shows FCC Data 79-007 and date 1980!
The first device is running about 3 minutes after the PLL rises from quartz 10,240 no longer vibrates and some voltages are missing. I suspect that a capacitor is defective! Nothing gets warm.

The 2 device runs at about 21 MHZ that shows at least the frequency counter, but has run but has stood a long time!
I hope that someone can help me.
Have changed the green VCO blog and the quartz on both devices without success!

[bernado]

Does nobody have an idea what could be?

[ch25]

Is there any schematic to see? Link it
What about VCO voltage, did you check it?
Chris

[cubwolf]

The 10.240 issue is the orange polyester cap next to the crystal.
C11 its a 560pf. They go short circuit and stop the 10.240 working.

[bernado]

I have a Service Manual i will chek tomarow some voltage and come back tomarow! Thanks for help!

[Otter]

You should check the capacitor that cubwolf suggests. He is a specialist in the repair of Cybernet SSB radios, and this is a common fault. Replacing C11 is the first thing that you should do. If that doesn't work, then check voltages.

[bernado]

Many thanks C11 was broken this is the first time that a ceramic capacitor was defective. But there are more errors I can adjust the voltage at the VCO block but for the middle band and the high band I can not match the voltage on VR1 and VR2 adjust.Q8 also seems to be defective. The quartz 10,240 I had to swap synonymous now can be the frequency again accurately. The output power is also only 2 watts AM FM and SSB 0.7 watts! There is still much work on the device! Thanks again I report in the evening!

Best Regards
Bernd

[bernado]

Hello, good morning!
Is there anybody who has a service manual specifically for this device? Mine is from the jumbo and is not quite true.
Best Regards
Bernd

[M1JWR]

As for the second radio, frequency counter will say 21.390mhz ? on every channel.
ive seen this before, its 10.965 mhz x 2, the power output cans have been screwdrivered way out of spec
they need re tuned back into spec, radio shoud still rx ok (hopefully)
should be nothing actually broken, dont have a schematic as this was on a 121 boarded radio.

[bernado]

Hello M1JWR
thanks for the Info i will test again the Radio