power supply induced madness

[towerdog]

So the last few days I been working on getting my station setup in my closet. Finally get it all put together and fire up the TS-440 and !@#!@$@#$, its acting like the line is shorted, redo connectors and VSWR is still !@#!@#:1, plus dots of death. Put a load at the end of the line, results still VSWR of !@#!@:1, put radio at the antenna, still !@#!@#@, check connections, still !@#!@#.

Hooked up the 440 to the load, still !@#!@##, my load is bad?
I figured enough before I screw my radio any more, and hook up an old 23 channel CB, hooked up to a smaller power supply. VSWR is now 1.2:1.
!@#!@#@!#.
Take the TS-440 and put it back in the truck, oh now it works!!! Yay.
Put the TS-440 back in the house, now it dont work, Noooo.

Check voltage on the PS-40 supply, 14.2v and the 440 still shuts off with VSWR of $#1&:1

Try hooking it up to a smaller power supply, and cut down the 440's power to 3 watts, now radio works with VSWR of 1.2:1.

2 partial days of hell all caused by a faulty psu likely putting out an AC voltage causing the 440 to throw harmonics and spurious all over giving the SWR bridge a bad reading.

Station is now up and running, missed the end of the sunspot by minutes but made local contacts on 38LSB.

What have I learned,

#1 digital VOM's are gay
#2 radios sometimes throw all sorts of harmonics and crap just like cheap amplifiers do

 

[Captain Kilowatt]

What have I learned,

#1 digital VOM's are gay
#2 radios sometimes throw all sorts of harmonics and crap just like cheap amplifiers do

#1-No, not really. They have their place and one should have and know how to use both analog and digital VOM,s. Both have advantages and disadvantages as well as limitations.

#2- Anything will malfunction sometimes especially when the power source is dirty.The difference in your comparison is that cheap amplifiers spew crap and harmonics ALL of the time.


So, in the end have the dots disappeared now that you have the power supply situation solved? Was the PSU really faulty or was it throwing fits due to RFI?

 

[wavrider]

TS-440's can be a peculiar rig at times. I have one, hamfest special guaranteed no issues. Yah right.

After much trouble shooting and repairs the rig finally works correctly.

Stable P/S is a must for the TS-440, or any ham rig for that matter.

As CK stated digital and analog meters both have there purpose, and they do function well for what they are.

An Antenna analyzer might have helped in trouble shooting your problems as it looked like it was an VSWR issue indicated when it turned out to be voltage/current problems.

Glad you got it figured out.

 

[mackmobile43]

try placing a .01 pf capacitor across the leads of the digital VOM to eliminate the RFi issue.

 

[Captain Kilowatt]

try placing a .01 pf capacitor across the leads of the digital VOM to eliminate the RFi issue.

Yep, that works about 99% of the time except in a really high RF field where the RF penetrates the case and messes with the electronics directly where no amount of filtering will help. I only had that happen at a couple broadcast sites but then again the analog meter would read whatever I wanted it to depending on how the leads were held and that was with a torroid on the leads and a capacitor across them.

 

[towerdog]

thats what happened to this VOM, was using it to align a dish and the wind blew the VOM around in front the dish, then i got rained on. resistance calibration has been way off since, although voltage still works.

I like an analog meter better for troubleshooting PSU's, you cant see a cap discharge or a needle swing from excessive ripple voltage with a digital.

Anyway the PSU might be an easy fix, if reference voltage is 13.8 and its getting 14.5 even under load, (is also regulated), I would say part of the rectifier is blown.

 

[pro151]

I use a Fluke 37 true RMS meter but still keep my trusty old Simpson 360 ready to go.

As said above, both meters have their places in the test process.

I also have a Fluke 337 True RMS Amp Clamp. Does direct DC amps.

 

[GnG8d]

thats what happened to this VOM, was using it to align a dish and the wind blew the VOM around in front the dish, then i got rained on. resistance calibration has been way off since, although voltage still works.

How is that the fault of the meter?

 

[towerdog]

its not