[Yaesu] Why are we so SWR-phobic

[N4AOF]

The rig designers are giving us the rigs "we" have told them we want to buy
- Solid state
-- High Power
--- Low cost

It would be possible to design a solid state rig that could withstand high 
SWR -- but doing so would increase the cost

Perhaps more importantly it would be bad for the company's reputation

If a company built a 200W solid state rig that could withstand the SWRs 
common in old tube rigs, it would be running the finals at much less than 
their full output power -- basically they would be building a 400W rig 
configured to operate at half-power into any SWR from 1:1 up to 2:1

That might suit you -- but I guarantee some ham would take one look at the 
circuit and figure out that a "simple mod" would let the rig put out the 
full 400W

Of course none of the circuitry would have been designed to do this, but 
that wouldn't stop hundreds of hams from making the "simple mod" -- and 
either burning out the finals into a 1.5:1 SWR or burning out some other 
component that wasn't meant to support the demands of the 400W finals. 
Either way, the manufacturer would be blamed for the rig not being reliable. 
No one would care that the rigs that were burning up were modded.  "We're 
hams, we have a right to mess around inside the rig!"  It would be the 
manufacturer's fault for making a rig that burned up when modified.

The only way to design a bullet-proof 200W rig, is to first design a 
complete 400W rig all the way through, then beef that up, then finally 
incorporate circuitry at every point to limit it back down to 200W to try to 
make it idiot-proof.

But who would buy a 200W rig that costs more than a 400W rig should cost?

----- Original Message ----- 
From: "John Geiger" <w5td at lcisp.com>
To: "ICOM Reflector" <icom at mailman.qth.net>; <kenwood at mailman.qth.net>; 
<yaesu at mailman.qth.net>; <dx-list at yahoogroups.com>; 
<cq-contest at contesting.com>
Sent: Sunday, June 18, 2006 18:16
Subject: [Yaesu] Why are we so SWR-phobic


Am I the only one who things that the SWR protection circuits in currents 
are ridiculous?  I mean, most of them start cutting power back with a 1.5:1 
SWR?  Are today's rigs so poorly designed that you could damage the finals 
with a 2:1 SWR?  Older solid state rigs used to handle that just fine.  The 
ad for the Yaesu FT107M advertised that it would put out 75% power into a 
3:1 SWR!!  Most Ten Tecs will put out almost full power into a 3:1 SWR.  But 
most other moderns rigs are putting out 50% power or so into a 2:1 SWR.

The worst is the Yaesu FT857/897 series which cuts up the audio if the SWR 
gets above 1.5:1 or so, and people think that this is a good thing?

So what is going on with the rig designers?  Do people really want this 
aggressive of an SWR circuit?  I find it kind of annoying to have to return 
the tuner every 25 kcs or so on some radios.  Are the finals today really 
that fragile?

Or is it just me?  Anyone else with ideas?

73s John W5TD
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