Jim Weir - Radio Receive Current

"Ron Wanttaja" wrote in message
...

The Escort 2 I replaced it with is rated just 0.5 amps during receive, and
the
ICOM IC-A5 that replaced *that* runs for hours on a set of AA batteries.
Were
those first-generation solid-state radios really that inefficient?

yes. back then no one thought about power efficiency.

"Tater Schuld" schreef in bericht
...

"Ron Wanttaja" wrote in message
...

The Escort 2 I replaced it with is rated just 0.5 amps during receive,
and the
ICOM IC-A5 that replaced *that* runs for hours on a set of AA batteries.
Were
those first-generation solid-state radios really that inefficient?

yes. back then no one thought about power efficiency.

It is true that power-efficiency wasn't a prime design factor
before the 90's or so. Even so, it would really take a lot of
bad sense to design a solid state nav TX drawing 2 amps
(that means 25 watts!) in rx standby or even active mode.
So, unhindered by much factual knowledge, I tend to agree
with O/P, somethings's wrong somewhere.

Humbly from continental Europe,
Karel.

those first-generation solid-state radios really that inefficient?


Around 1978, I was given the job of modifying a Motorola Land Mobile (FM
~150MHz) repeater for use on a mountaintop repeater site where we were
installing solar power. The idea was to see how much current we could save
with simple modifications.

I found that when you turned the speaker off with the little plastic slide
switch provided, it actually SHORTED the output of the audio transformer.
Shut the thing up - sure did! So 90% of the standby rx current was being
drawn by audio circuitry - just because the design people had been too cheap
or lazy to do it right. And this was on a fairly modern (by aviation
standards) radio that was worth $5000 or so, even back then.

I moved the switch so that it cut power to the audio instead of just
shutting it up - and the size of the panels needed dropped by half!

You said they didn't care about current draw. That may have been an
understatement!