On Oct 22, 2006, at 3:52 AM, pentalab wrote:
--- In ham_amplifiers@..., R L Measures <r@...> wrote:
RICH SEZ.... W8JI's censorship is quite rational, Bill.
R L Measures, AG6K, 805.386.3734
r@..., , rlm@..., www.somis.org
#### I had sent an e-mail to Rauch re: this PEP vs Average
nonsense on the "other reflector". Other's had mentioned texts
where they depict 14.5 db peak to average ratio in the male
voice. I looked it up... it's also in "SSB sytems and
circuits"... same deal.. 14.5 db. What every one missed was
they are talking about absolute peak... as in ur 100 watt rms bulb
is actually 200 peak.... and your 120 vac is actually 169.7 V. Peak
V / dc resistnace = peak current. Peak current x peak V =
peak watts.... that kinda peak.
To me, that Is peak P.
### Reading though some audio engineering notes.. it was pointed
out that a pure sinewave had a ... 3db peak to average ratio....
then the light bulb went on ! I tried the same experiment on
my Behringer DEQ-2496 built in RTA... and sure enough, a sine wave
has exactly 3db peak to rms ratio.
Agreed, which is why 1500W-pep is 3000W-peak as measured on an oscilloscope and calculated from P = E^2 / R.
When talking on my RE-27
mic... and looking at the raw audio on the RTA [b4 processing it
with EQ, compression, split band limiter's, etc] I get EXACLY
14.5 db peak to rms ratio. This rta will hold the highest
peak too... and in 1/10 db increments.
### How does this relate to ssb + linears ? While looking
at my L4B's plate current meter.... with a dead cxr.. reads 800
Ma. While talking, it averages around 350-370ma...
I would turn down the mic, gain if my pair of 3-500Zs indicated this much anode-I.
and 400-420
ma with the processing on. Looking at the Coaxial Dynamic's
wattmeter... with a dead cxr... reads 1250 w. [whether meter is
switched to average OR pep] While talking.[processor
OFF]..and meter on average.... meter reads aprx 175- 200 w .
Switch to pep.... reads 1400 w. With processor ON... pep readings
are the same 1400 w pep. Switch to AVERAGE... and meter reads
250-265 w 1400 w pep / 250 average = 7.48 db IE: the
average power output [250 w], is 7.48 db down from pep...
and 7.48 db = 14.96 db peak. 14.96 db peak is virtually
identical to the 14.5 db peak to rms ratio I measured on my audio
rta in the 1st place !!!!!
### Imo.... the confusion arises between interpreting plate
current readings while talking [with varying meter response time
constants between different brands of linears/plate meter's]....
and interpreting wattmeter readings, while talking... and
wattmeter switched to "average". Of course, you can take 5 x
different brands of wattmeter's... calibrate em all so they all
read exactly 100 w with a dead cxr. Feed ssb into em [all 5 x
wattmeter's on average... and all wired nose to tail]... and they
all indicate differently ! Flip the processor on and off, and
some average reading wattmeter's will show the increase in
average more than other's ! Probably to read true average, a RF
thermocouple ammeter would be the ticket.
correctomundo
### Below is Tom Rauch's response.
Hi Jim,
Please don't attempt to be civil to my face and a horse's ass in
public about me on that Google amplifier hate group.
We definitely do hate censorship, Tom.
The current situation reminds me of a neighbor boy who wanted to play games at his house with other neighbor boys, but he makes up rules to help him win, and then gets mad because the other boys left.
Please be one way or the other. I have a rule where i treat people
exactly the same behind their backs as I do in their face. I expect
the same.
What a laugher. He pretends not to be the Administrator/censor, yet he knows the excuses why those who question his questionable technical statements get booted off of AMPS before it's announced.
Thanks,
Tom
### Apparently Tom reads the posts here... and myself and other's
must have either (a) pissed him off (b) he doesn't like
criticism leveled at him
Exactly. Because the subject is so involved, a smart TX RF amplifier debater:
1. Keeps his mouth on standby unless he knows the area of discussion.
2. When he inevitably makes a blunder, he is blazingly quick to admit to it and thank whoever gave the correct analysis.
3. Does not declare that he is one of the "recognized experts".
(c) doesn't like "bad mouthing" about
his Ameritron/ Heath/ Dentron /Amp supply/ MFJ 'engineering'
MFJ has a rather well deserved reputation as the junkiest commercially built Hamstuff on this planet. I have heard numerous Hams refer to it as Mother F___ing Junk. Also, as I understand it, an MFJ "3000w" antenna tuner was the only one ever tested in the ARRL Lab to ignite at 900W.
One of the best laughers I heard from Tom was his assertion that MHJ/Ameritron amps don't have a glitch-resistor because the filter caps they buy have so much ESR built right in that they can't produce enough peak current to damage a tube.
or
(d) doesn't like the idea that he will never post here,
I hope he does post here. If Tom is not allowed to post here, I'm outta here.
and
can't do his own rebuttal (e) can't defend the superb
engineering of Ameritron products.... like the AL-1500's 8 x
lytics being run at their MAX + voltage ratings... then
saying "that's ok" .... "just make sure the bleeder eq
resistor's don't ever open up, or the lytics WILL start blowing
up en masse" [If u ran the lytics at the prescribed 75%
max V rating the manufacturer's recomend, they will NOT blow up, if
the bleeder EQ resistor's open up.]
I'll bet a medium pizza with 5 toppings that I can show an example where a 75% safety factor would cause a serious problem if a bleeder- R opened.
### Heck... anybody can read the posts, without being a member...
they just can't post.. or see photo's, etc. He could log in with
ANY user name... and ANY hotmail address. My guess is... he is
probably among us right now.
good news
### Here's my reply to Tom... dated a few day's ago.
### agreed. The other group isn't any hate group.... it runs
just fine since day 1. You are free to join in any time you
want. Loads of pix on there too.
### I use some of your insights as examples from time to time...
like the test jigs for testing 3-500Z's for shorts... tripped
leds the next AM..stuff like that.
### In the case of poorly designed Palstar /Ameritron / anybody
else's products... they are fair game.
### we all know who the secret administrator is now.... it's Joe
Subich W4TV.... blatantly obvious now.
Not a sound wager. The only thing we know for sure is that Tom is the first to provide the reasons (excuses) why someone got his posterior jackbooted off of AMPS, and that anyone there who questions Tom's technically questionable statements is stepping into deep feces.
### Nothing is behind your back.... it's a public forum.... with
136 members.. and growing in leaps and bounds.
### If member's can't freely disagree or discuss things...
what's the point ?
A discussion group that is not allowed to discuss certain things is very clearly meshugga/bananas/nuts.
cheers, Jim
Take care.... Jim VE7RF
####### On the surface, this doesn't appear to be a .. "Google
amplifier hate group". This Tom Rauch scenario appears to be
nothing more than... 'sour grapes'. Me, I could afford to go
out and buy 6 x Ameritron's right now, cash.... but don't. If
they were any good, I'd have a few of em here in 4 day's flat.
I'm tired of fixing this crap for other fellows. I got fed
up with what's available for amateur radio... decided to build
it myself. Next trick was most of the various handbooks lack
detail. I found 38 mistakes...so far [mostly typo's] in Orr's
23rd and latest edition [and still available]. And that's
only a fraction of that book. The 2006 ARRL handbook has a
poorly written section on tube amplifiers. Bought a few
engineering text's as well. The fellows who wrote the latest
edition of "SSB sytems and circuits" obviously have a 'hate
on' for GG linears. If it's not grid driven, it's no good..
per the Collins engineers. [who wrote the book].
### gave up on standard texts... and decided to undertake a long
drawn out study of every last component in a GG linear, it's
function, calculated peak/average voltage + current of
everything.... do a series of bench tests... and prove one way or
another new concepts. Several idea's were tried, some
discarded, some although they work superbly, are way too complex,
and would make construction, implementaion, and trbl shooting and
repair more difficult. I call the 'whittling down'
process...'the elimination program'. Don't stick 4 x
sockets/tubes/chimney's/anode suppressor's in an amp..... when
just one socketless tube will do the job. You don't stick 4 x
engines under the hood of a car... u get a bigger engine to start
with. Trying to split the drive 4 x equal ways, ditto with
airflow, then 4 x independently adjustable regulated bias
supplies... + 5 x switchable plate current shunts [individual +
total] amounts to a nightmare in progress. [you require
separate fil xfmr sec's as well] Trying to trbl shoot a multiple
tube amp with one bad int tube is a horror show.
## The short of it, with a HB amp... or at least a modified
commercial unit... you can get some satisfaction from the
process. When u light the wick on a HB amp for the 1st time,
get any bugs resolved... and watch the wattmeter get blown off the
scale.. it's a feeling of imense personal accomplishment and
achievement. You don't get that with stock commercial units.
### I'm trying to convince W7IUV to resurect his 'amp pix
page' from years ago. That alone inspired more people than
anything else imo. It had 10's of thousands of hits from around
the planet... including US signal corps, Nasa, and other's. It
really showcased what ham's were doing in their work shops... and
no two looked alike.
Outa here... stay tuned...... Jim VE7RF
Yahoo! Groups Links
R L Measures, AG6K, 805.386.3734
r@..., , rlm@..., www.somis.org
