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Author Topic: Your favorite antenna wire.  (Read 41910 times)
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K1JJ
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"Let's go kayaking, Tommy!" - Yaz


« Reply #50 on: July 23, 2011, 05:33:02 PM »

Yep, maybe we are talking more like 900w on standby with the 4X1 - what a pig!    Shocked

The class E rig's limitation is QSY, though some have conquered that.  I am able to QSY from 3885 down to 3725 by just turning C1. (and the VFO, of course)  It puts out full power there and the waveform looks FB.  But it is a one band rig for 75M.

Others just use the same infrastructure and switch in a different RF deck. Pretty easy. Still, others are switching bands using little high-curent relays to add padding caps, etc. I know of at least three that do 160/75/40M with a flick of the switch.   However, 20-10M is still limited by the MOSFET devices not being cheap.

With the new VFO/digital drive system, the overall RF deck has become quite stable and indestructable. Even I haven't lost an RF strip yet in 18 months of opertation. That's saying something... Grin

T
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Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
KM1H
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« Reply #51 on: July 23, 2011, 05:37:40 PM »

It might be useful on 600M, can they handle CW and data modes as well as AM and SSB?
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kg8lb
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« Reply #52 on: July 24, 2011, 05:13:21 PM »

Yep, maybe we are talking more like 900w on standby with the 4X1 - what a pig!    Shocked

The class E rig's limitation is QSY, though some have conquered that.  I am able to QSY from 3885 down to 3725 by just turning C1. (and the VFO, of course)  It puts out full power there and the waveform looks FB.  But it is a one band rig for 75M.

Others just use the same infrastructure and switch in a different RF deck. Pretty easy. Still, others are switching bands using little high-curent relays to add padding caps, etc. I know of at least three that do 160/75/40M with a flick of the switch.   However, 20-10M is still limited by the MOSFET devices not being cheap.

With the new VFO/digital drive system, the overall RF deck has become quite stable and indestructable. Even I haven't lost an RF strip yet in 18 months of opertation. That's saying something... Grin

T

And that is AWESOME !
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K1JJ
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« Reply #53 on: July 24, 2011, 05:55:41 PM »

It might be useful on 600M, can they handle CW and data modes as well as AM and SSB?


Carl,

On the VLF bands the guys appear to favor the class D rigs over the E rigs for digital/cw modes.  The layout is simpler for class D and QSYing is just like using a class C rig.  Jay/W1VD is the guy to axe about this.  I'm not sure if he has ironed out issues related to combining class D modules yet. Some of the big logs are running serious power up there solid state.

Steve/QIX favors the class E rig for HF. I don't recall the reasons why over class D, though Jay has an excellent sounding class D 300w? AM rig on HF.

I don't see why a class E rig cannot handle any signal application related to non-linear operating, like digital, CW, FM, etc.  AM requires a PDM or analog modulator. SSB would be a problem since it would need a linear amplifier or digital switching scheme of some kind.

T

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Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
N2udf
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« Reply #54 on: July 25, 2011, 10:46:58 AM »

I haven't had breakage with a #13 copper covered steel with insulation.It is available from the Wireman and others....Lee,N2UDF.
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