Tom, I hear your concerns.
Back in the old days, that was called a "side tone".
The odd thing is if the vibration increases at the same level at 5 watts and
100 watts.
More current draw the more the vibration, but much less current is being
drawn at the lowest power levels.
That kind of a hum is how I tuned my valiants for 25 years.
Before k9vcn built me an audible oscillator, I used an old stethoscope for
accureate tuning.


-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Tom Behler
Sent: Saturday, December 12, 2015 2:01 PM
To: [log in to unmask]
Subject: Re-thinking New RS35 Power Supply Issue Again

Hello, again, everyone.

 

I am now beginning to wonder if today is my day for Murphy to make a visit
here, or just what exactly the deal is.

 

I was working a bit of the 10-meter contest today, and noticed a further
problem with the hum issue on my new Astron RS35 power supply.

 

I'm not sure why I didn't notice it last night when I did my testing, but
now, I find that whenever I transmit in CW at any power level-i.e. 5 watts
or 100 watts, the hum on the RS35 slightly increases.  In other words, when
I key down, I hear a slight, but noticeable increase in the hum at any power
level.

 

So, now, I'm trying to decide whether I actually should return the supply to
H R O.

 

I have my receipt and all other documentation, but I'm wondering whether the
folks at HRO would see this as a significant enough of a problem for a
product return.

 

The supply still seems to carry the load ok, and does put out what I would
expect in terms of output power readings, but the hum issue is a noticeable
one now, on several counts.

 

I don't mean to be obsessive about this, but I wouldn't expect to be dealing
with this sort of issue with a newly-purchased power supply like this.

 

I'd continue to be interested in anyone's thoughts.

 

Tom Behler: KB8TYJ