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I have an Alinco dx-70 that has 2 problems. The radio receives on all bands execpt 6 meters just fine. The radio will not put any rf power out or receive on 6 meters at all, though I can hear my self in my police scanner when the scanner is set for a 6 meter freq and I can inject a siginal from a rf generator on the same 6 meter freq and hear it. The other problem is the radio needs 15 vdc from the power supply before it will transmit on the hf bands at all. As the voltage drops below 15 vdc the power out drops, and by the time the voltage is down to 13.5 there is no power out left. I have a 30 amp continuous duty varable voltage regulated power supply. On max power out the manual tells me the radio draws 25 amps.
Can anyone please help me with these problems.

hi well this may sound stupid but your not gonna hear anything on six unless the band is open or if you have local activity on six second i would wonder if the meter on the power supply is acurate and a realy stupid questition is do you have an antenna hooked to the six meter ant port ??? the hf antenna port does not work on six
just my two cents worth

cnuck

Yes I have checked the output of the power supply with a digital volt meter, and the volt meter was connected to the supply line during the test. As for not been able to receive on 6 meters. I know about the 2nd 6 meter jack on the back. An antenna is connected to the 6 meter jack. And I could not hear anything when the band was wide open and active durning the last solar burst.

ok that answers that now have you checked to see if the coax might be shorted
on the six mtr ant ??? the signal generator you used does it have a calibraited
output ???? if it does you should have about .1 mv sensitivity if it is more than
that you might an rf amp transistor bad on 50 mhz .... read the power requirement specs in the manual ..... also check the internal power setting to see if it is set in the 50 watt mode slide switch inside rig ...... by the way do you have the th or the t model

chuck

1st it says on the front just dx-70 there is no " T " or " TH " after the 70.
There is no coax on the antenna connecters. The antenna connectors are directly hard wired to the pc board and bolted down.
My rf generator is an old tube job and the calabration is not very good.

i ment the coax coming from the antenna is it shorted or open ???
the t model is only 10 watts on six the th model is 100 watts on six you will not show any output on six ssb unless you talk check six mtr output in fm mode do you have out put then ???

chuck

The coax is ok. There is no rf output in any mode on 6 meters. Do you got any ideas on the supply voltage problem?

NOPE I AM FRESH OUT OF IDEAS

73 CHUCK

wa4cch wrote:NOPE I AM FRESH OUT OF IDEAS

73 CHUCK

BANDPASS diode?????? Alinco can fix it

Hi Steve, I have had 4 DX-70's and all of them loved voltage. I had to run a 35 amp power supply at all times so the audio wouldn't be gargled on transmit. I had one in my van and it wouldn't work hardly at all unless the engine was running. I dont have a clue whats going on with your 6 meter part unless it needs more voltage and amps. Believe me Steve their super hungrey for voltage and amps. Guess its just the way their designed, keep em fed and they run great.
N8CWR