Homebuilts and radios!

First Sid
Look closer at the post I was not the one making the post about the
attenuator. I made the post about the amps/power consumption of the unit.
The original poster made the att. comments. These threads can be confusing
at times!
;-)

That being said your answer is YES it could. Especially if the unit was run
for too long a time the equipment could be designed to handle continuous
power of 30 watts but the 47 watts would cause thermal runaway and
eventually burn it up. Also with a 50 ohm circuit and 47 watts the output
would be 48 volts rf, with 30 watts it would have 30 volts. I the unit had
voltage sensitive devices in it between those two voltages it could very
well pop it immediately.
So Craig could be giving you the correct skinny (or he could be blowing
smoke (pun intended)) you really would have to know the spec's of the
equipment to know for sure.
John





sidk wrote:

John wrote:
Craig wrote:

Part of it is probably due to the fact that Motorola rigs are well known
for actual RF output _well_ above the 'nominal' output. I used to use a
nominal 30 watt VHF hi-band unit where the actual RF out was just over 47
watts. Every time I took it into the radio shop to have the cavities
tweaked,
they insisted on doing a TX test. *Despite* my warning them about the
output
level, they'd blow the attenuator on the test instrument every time.
After the puff of smoke, the urge to say "I told you so" was nearly
overwhelming.

Uhh, John... 47 Watts is barely 2 dB greater power than 30 Watts.
Are you saying that they had a piece of equipment that could not
handle a 2 dB overload and would "...blow the attenuator on the test
instrument every time." ???
Further, an attenuator designed for a nominal 30 Watts would have a
fairly substantial mass or a lot of forced-air cooling. An additional
2 dB would make it go up in a "...puff of smoke.." ???

Sid Knox

Velocity N199RS
Starduster N666SK
KR2 N24TC
W7QJQ

John wrote in message ...


a bunch snipped from here....



So Craig could be giving you the correct skinny (or he could be blowing
smoke (pun intended)) you really would have to know the spec's of the
equipment to know for sure.
John



'Cept it wasn't me talking about smoking equipment..... I haven't
smoked a piece of test gear other than a couple of Simpson VOM's since
getting out of tech school in '81.

Craig C.