TS-480 Audio Fixed

[k6biv]

Hello All:

Well I got to the bottom of my audio issue today.

In July, when we installed the Remote Rig, I had made the audio modification on the RRC "head unit."

I got a "world class" Heil PR40 with the boom and everything. I added a PreSonus TubePre, EQ3B and a Comp 16 to my mic input. I was going to be 10-8 on all bands.

We installed OCF wire antenna @ 3800' on the top of Mt. Diablo in Northern California. I have a 5.8G connection directly between my house and the hill. Nothing was going to keep me from being a BMOC.

Well, now what happened...

I had a great crew to assist with the install and everything "looked" good, but the audio was horrible.

Anytime I went over 10 watts of power it would go to hell..

I have a 100 amp N+1 power supply, so I knew I had enough power for a 100 watt radio.

It turns out the TS-480 was connected to the "battery backup" terminals of the PS and on key-up voltage would drop to about 9VDC and a "hum" could be heard.

Well it is now fixed and working well..

So in the end, pilot error again.

Thanks,

Tim

[K7FD]

Thanks to Tim's post and this forum, I was quickly able to pinpoint a solution to a new problem that arose today: motor boating hum on transmitted SSB audio.

I have been using a gel cell battery to power the control RRC while operating portable from my RV. Today I received poor audio reports from the Kenwood TS-480SAT...

After reading Tim's post, I had one of those 'aha!' moments and immediately checked the battery voltage. Lo and behold, 9.9V. As soon as I plugged into steady 12v shore power, no more motor boating hum on the audio. Time to make sure that gel cell gets a good charge and to monitor the voltage during use!

73 John K7FD