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Old September 30th 06, 09:32 PM posted to rec.radio.cb
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Posts: 985
Default Griffey changes his mind...derates to 322 watts PEP

Premium Quality PC Board, Components and Chassis
13.8VDC
10 Meter Amateur Radio Band Coverage
All Mode (CW, AM, FM, SSB)
Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched
Transistors
Regulated Class-AB Biasing
High Output Power
High Efficiency Heat Sink
Polarized Detachable Power Cord
Fuse Protected
Extremely Low Stand-By Power
Remote Operation Ready
Carrier Operated Relay (COR) or Multiplexed Keying†
SSB Delay to Eliminate Relay Chatter
High Reliability Design
Low Harmonic Content
90 Day Limited Warranty
† Contact Telstar Electronics for details on using this feature

www.telstar-electronics.com

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Old September 30th 06, 10:24 PM posted to rec.radio.cb
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First recorded activity by RadioBanter: Jul 2006
Posts: 432
Default Griffey changes his mind...derates to 322 watts PEP

On 30 Sep 2006 13:32:13 -0700, "Telstar Electronics"
wrote in
. com:

Premium Quality PC Board, Components and Chassis
13.8VDC
10 Meter Amateur Radio Band Coverage
All Mode (CW, AM, FM, SSB)
Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched
Transistors
Regulated Class-AB Biasing
High Output Power
High Efficiency Heat Sink
Polarized Detachable Power Cord
Fuse Protected
Extremely Low Stand-By Power
Remote Operation Ready
Carrier Operated Relay (COR) or Multiplexed Keying†
SSB Delay to Eliminate Relay Chatter
High Reliability Design
Low Harmonic Content
90 Day Limited Warranty
† Contact Telstar Electronics for details on using this feature

www.telstar-electronics.com



Hey Brian.....

Since the transistors you are using are rated for a typical gain of
15.2dB, and you are using two of them, why is your amp rated for only
15dB instead of 18.2dB?

And at 18.2dB, if you shove in a typical 4 watt carrier from a CB,
doesn't that put your AM "RMS" output about 264 watts? (And your PEP
output at 1056 watts?)

Now assuming you have a magical amp that can achieve 55% efficiency
irrespective of the 35% collector efficiency of the transistor, when
you 100% modulate this 264 watt carrier (giving an AVERAGE power 396
watts), doesn't that mean you are going to be drawing 720 watts from
your power supply?

Just in case I missed something in 3rd-grade math you better check my
work he 720 watts / 15 volts = 48 amps. You also have a base-bias
current of 1 amp for each transistor, so 48 + 2 = 50 amps. Right?

But who uses a 15 volt power supply? Heck, we'll use the more common
automotive standard of 13.8 volts. So 720 / 13.8 = 52.2 amps, plus 2
amps = 54.2 amps.

HOLD ON A SEC.... Your amp only has a 30 amp fuse!!!

So after I get this all hooked up, wired directly to my battery and
everything, plug in my favorite little 4-watt CB, this amp is going to
blow a fuse every time I yell "A-U-D-I-O" into the mic.

Ok, I bypass the fuse and switch my CB on SSB with 12 watts PEP.
What's going to melt first -- the transistors or the power leads?

And you call this a "High Reliability Design"....."LOL"!!!




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Old October 1st 06, 02:56 AM posted to rec.radio.cb
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Default Griffey changes his mind...derates to 322 watts PEP

On 30 Sep 2006 15:07:00 -0700, "Pouting Brian"
wrote in
. com:

On Sat, 30 Sep 2006 14:24:22 -0700, Frank Gilliland wrote in :

Hey Brian.....

Since the transistors you are using are rated for a typical gain of
15.2dB, and you are using two of them, why is your amp rated for only
15dB instead of 18.2dB?


Because I attenutated the input, which gives the amp an overall gain of 15dB.



Well that doesn't make sense -- why use two transistors in an amp that
can be built with one? Aren't you the one that's always worried about
it being too expensive?


HOLD ON A SEC.... Your amp only has a 30 amp fuse!!!

So after I get this all hooked up, wired directly to my battery and
everything, plug in my favorite little 4-watt CB, this amp is going to
blow a fuse every time I yell "A-U-D-I-O" into the mic.


You are a real idiot if you don't know about slo-blow fuses.



I took that into account, Pouting Brian. That's why I calculated
AVERAGE power and not PEAK (PEP) power, just like it was outlined in
your favorite educational website.


Ok, I bypass the fuse and switch my CB on SSB with 12 watts PEP.
What's going to melt first -- the transistors or the power leads?


Your brain, but it melted a long time ago.



Good comeback, Pouting Brian..... I feel like I have been dissed by
the best...."LOL"!!!


And you call this a "High Reliability Design"....."LOL"!!!


Where's your amp, Frank?



That's what it all boils down to with you, isn't it?

You get up on the stage and sing like a rutting moose. When you are
done, the audience stops grimmacing and takes their fingers out of
their ears, and they begin their criticism. You can't take it so you
try to turn your lack of ability onto them by saying, "Let's hear YOU
sing." A classic 'sour grapes' response.

You built an amp without any engineering ability and it shows. If you
don't like the criticism, get off the stage. Otherwise, get ready for
the rotten tomatos because there are plenty more things I can pick
apart about your amp from your spec sheet..... for example, did you
know that total harmonic distortion can be calculated from an amp's
nonlinear response? And guess what: you posted the curve!

So get ready for round 2....."LOL"!!!



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Old October 1st 06, 02:00 PM posted to rec.radio.cb
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First recorded activity by RadioBanter: Jul 2006
Posts: 985
Default Griffey changes his mind...derates to 322 watts PEP

SkyWave 2879AB RF Mobile Linear Amplifier

Premium Quality PC Board, Components and Chassis
13.8VDC
10 Meter Amateur Radio Band Coverage
All Mode (CW, AM, FM, SSB)
Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched
Transistors
Regulated Class-AB Biasing
High Output Power
High Efficiency Heat Sink
Polarized Detachable Power Cord
Fuse Protected
Extremely Low Stand-By Power
Remote Operation Ready
Carrier Operated Relay (COR) or Multiplexed Keying†
SSB Delay to Eliminate Relay Chatter
High Reliability Design
Low Harmonic Content
90 Day Limited Warranty
† Contact Telstar Electronics for details on using this feature

www.telstar-electronics.com

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Old October 1st 06, 02:35 PM posted to rec.radio.cb
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Posts: 123
Default Griffey changes his mind...derates to 322 watts PEP

On 1 Oct 2006 06:00:36 -0700, "Telstar Electronics"
wrote:

SkyWave 2879AB RF Mobile Linear Amplifier
Stability issues passed dow to the amp from the builder

Premium Quality PC Board, Components and Chassis
13.8VDC
10 Meter Amateur Radio Band Coverage
All Mode (CW, AM, FM, SSB)
Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched
Transistors
Regulated Class-AB Biasing
High Output Power
High Efficiency Heat Sink
Polarized Detachable Power Cord
Fuse Protected
Extremely Low Stand-By Power
Remote Operation Ready
Carrier Operated Relay (COR) or Multiplexed Keying†
SSB Delay to Eliminate Relay Chatter
High Reliability Design
Low Harmonic Content
90 Day Limited Warranty
† Contact Telstar Electronics for details on using this feature

www.telstar-electronics.com



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Old October 1st 06, 08:32 PM posted to rec.radio.cb
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First recorded activity by RadioBanter: Jul 2006
Posts: 432
Default Griffey changes his mind...derates to 322 watts PEP

On 1 Oct 2006 06:00:36 -0700, "Pouting Brian"
wrote in
.com:

snip spam

Good business strategy, Brian -- if you don't say anything, you can't
be proven wrong or give further demonstrations of your incompetence.
The only problem is that the damage has been done, and your posts are
now nothing but pure spam. But hey, if that's what you think will sell
your splatterbox then by all means go for it..... "LOL"!!!







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Old October 2nd 06, 03:09 AM posted to rec.radio.cb
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Posts: 1,054
Default Griffey changes his mind...derates to 322 watts PEP

Frank Gilliland wrote:
On 1 Oct 2006 06:00:36 -0700, "Pouting Brian"
wrote in
.com:

snip spam

Good business strategy, Brian -- if you don't say anything, you can't
be proven wrong or give further demonstrations of your incompetence.
The only problem is that the damage has been done, and your posts are
now nothing but pure spam. But hey, if that's what you think will sell
your splatterbox then by all means go for it..... "LOL"!!!

Brian is about to get booted from another isp for flood/spam. "LOL"
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Old October 1st 06, 01:26 AM posted to rec.radio.cb
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Posts: 4
Default Griffey changes his mind...derates to 322 watts PEP


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