Small VHF Transmitter...

[Fox\'s Mercantile]

On 9/2/20 1:56 PM, Michael_A_Terrell wrote:
> One thing that wasn\'t mentioned. The output level is +35 to +45 dB.

Might wanna look at what ever you were looking at again.
The output as specified in the manual is +40 dBmV. NOT dBm.
The correction factor is -48.75, so the actual output in dBm is
-8.25 dBm. Or, about, 0.15 miliwatts.

I seriously doubt this modulator puts out 31.625 Watts.




--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Michael_A_Terrell]

Fox\'s Mercantile wrote:

On 9/2/20 1:56 PM, Michael_A_Terrell wrote:
One thing that wasn\'t mentioned. The output level is +35 to +45 dB.

Might wanna look at what ever you were looking at again.
The output as specified in the manual is +40 dBmV. NOT dBm.
The correction factor is -48.75, so the actual output in dBm is
-8.25 dBm. Or, about, 0.15 miliwatts.

I seriously doubt this modulator puts out 31.625 Watts.

I seriously doubt that you\'ve ever built any CATV head ends. I
expressed the output stage gain in dB, not dBm. Working in system
design, you work with gain and attenuation levels, not dBmv, dBm or any
other variation. To get the gain required for a line amp, the module
dissipates real power in Watts, not puny mW. Those modules are mounted
on a heavy bar that is bolted to the amplifier\'s case to dissipate that
heat. If you overdrive the input on a TV, you can damage the input
amplifier. At the very least, intermod and sync compression happens when
the tuners are overdriven. One system had over 10,000 TVs connected to it.

The systems that I worked with in the Military used Jerrold tube
based CARS to link two channels to every airfield around Ft. Rucker.
That system could also take control of the civilian CATV system at the
point where it entered the base. This was t allow emergency weather
alerts, or disaster information to be sent into the housing areas.

When I built an interface to connect two incompatible Community
loops, our lead tech radioed the office to complain that my design was
off. By just under +0.2dB. Not dBm or dBmv, but dB. Cable losses,
connector losses and insertion losses for passives is what eats up your
gain budget.

I wrote software back n the early \'80s to simplify system design.
Our company specification was +10 dBmv at the output port of the tap. In
most cases, that allowed four TVs and the drop loss at the highest
channel. The software stored data for every brand of coax we used for
feeder, trunk and super trunk. It held the specs for every brand of tap
for the feeders, so all you needed was an accurate strand map to design
a reliable and flat system.

The only thing that it couldn\'t do was stop lazy techs from changing
taps to drive more TVs in some homes. That dropped the signal for every
drop past that point. Johnny Bench was one of our customers. We had
drops to both ends of his home, and one TV was on a floating bar in his
pool.

I not only did system design, I maintained the microwave equipment.
Rockwell-Collins had soaked the industry for a crappy, modified fixed
tuned model that was a downgraded Military design. They ran so hot that
the PC boards would burn, and they refused to repair them. The design
was so bad that they used a 1500uF electrolytic in the video output
stage, rather than a properly designed amplifier that could handle the
DC offset. That series was listed as impossible to use with the
Videocypher II descramblers. I had already removed a trap from all of
them, because they didn\'t work with any channel carrying a secondary
service as a subcarrier.

The idiot manager freaked out, but he wasn\'t as smart as he thought
he was. He would set the Sat equipment up to output the 1V of video,
without terminating the Tektronix 528 waveform monitor. Then he had to
crank the modulator gain wide open to come close to 90% of noisy video
modulation. He claimed that Tektronix didn\'t know how to design test
equipment. Those Rockwell-Collins receivers had a 225 ohm resistor in
series with the output, so he was setting them for .25 volts of video.


For anyone who is interested in this subject, Blonder Tongue
publishes handy reference books. This is an older edition that still
covers NTSC equipment.

That large system had a RCA headend that was miswired at their factor.
When you tried to use the emergency alert system, all the outputs
dropped by just under 40dB. They had wired a splitter wrong. One port
work, the other didn\'t. Once again, the pointy haired boss insisted that
RCA NEVER made mistakes. I not only fixed that, but I modified it so the
individal Hetrodyne Signal Processors could detect a lost input and
switch to the auxilary IF inputs. These were fed by a single modsulator
with no upconverer. I used a spare video output from a character
generator to display, \"This channel is off the air. Please consult your
program guide.\" During an emergency that message was automatically
switched out for a different video feed. This eliminated a lot of phone
calls from customers, and it only took a dozen 1N4001 diodes.

The line, bridger and extender amplifiers were Sylvania, which was
sold to Tekscan. The original taps were built in Canada by Lindsay. They
were absolute shit. Instead of a cast face plate and water tight seals,
it used cheap chassis mount F connectors which were tinned brass, and
mounted on a pot metal face plate. They corroded quickly in the
Cincinnati area, thanks to road salt. That caused all kinds of intermod,
system leakage and poor signal quality.

<https://www.blondertongue.com%2Fpage%2Fmedia%2F2014_BRG_lo-res.pdf>


Stick to your used business radios, where you can do that simple job.

--
Never piss off an Engineer!

They don\'t get mad.

They don\'t get even.

They go for over unity! ;-)

 

[Fox\'s Mercantile]

On 9/4/20 7:09 PM, Michael_A_Terrell wrote:
> Stick to your used business radios, where you can do that simple job.

Ya know what? Go fuck yourself.
Nobody gives two shits about what you claim to have done.

And your entire post was just a bunch of non-related crap.

I have the manual. It clearly stated the output in dBmV.
I used to use it with a DVD player supplying video and audio to it to
show off various vintage TV sets in shop.
There was never any sign of overloading.

The crown jewel was my 1948 Andrea Sharp Focus VK-12 that I restored.
AM/FM and channels 1-13.

The only concern I have, is that 0.15 mW of output power it might not
have the range necessary



--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Michael_A_Terrell]

Fox\'s Mercantile wrote:

On 9/4/20 7:09 PM, Michael_A_Terrell wrote:
Stick to your used business radios, where you can do that simple job.

Ya know what? Go fuck yourself.
Nobody gives two shits about what you claim to have done.

Take your own advice. You\'ve done it to yourself, for years.

And your entire post was just a bunch of non-related crap.

That\'s your standard response when you are caught out.

I have the manual. It clearly stated the output in dBmV.

Of course it is. It is a signal SOURCE. They write the specs that
way for the simple minded. Modulators are intended to be a component in
a system. As a stand also device, the output would be much lower. In the
range of +3 to +6 dBmv. The combiner panels use a lot of the extra power
gain to overcome their insertion losses. Our head ends were flat to a
fraction of a dBmv at 20, leaving the building. Each trunk amplifier
raised it to reach the next amplifier at +20dBmv from 54 to 300 MHz. I\'m
sure this is all gibberish to you, because you don\'t ever admit that you
are wrong.

I don\'t know what happened to you after you moved out of California,
and I don\'t want to. Prior to the move your actually tried to help
people, instead of being a total waste of skin and oxygen. If I was as
miserable as you, I would either get help, or step in front of a semi on
the interstate.

I used to use it with a DVD player supplying video and audio to it to
show off various vintage TV sets in shop.
There was never any sign of overloading.

The crown jewel was my 1948 Andrea Sharp Focus VK-12 that I restored.
AM/FM and channels 1-13.

The only concern I have, is that 0.15 mW of output power it might not
have the range necessary

Then build a 100KW linear for Peter. Most of the old VJF spectrum has
been realocated. You don\'t want to get cught running too much power on
those frequencies. Not that you would give a damn.

--
Never piss off an Engineer!

They don\'t get mad.

They don\'t get even.

They go for over unity! ;-)

 

[Fox\'s Mercantile]

On 9/4/20 11:17 PM, Michael_A_Terrell wrote:
> [ Nothing worth quoting ]

Exactly what I\'d expect from you.
More non-related crap.
And and implied death threat.

You\'re pathetic.


--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[ohg...@gmail.com]

On Tuesday, September 1, 2020 at 4:29:43 PM UTC-4, terrell....@gmail.com wrote:

ohg...@gmail.com wrote:
On Tuesday, September 1, 2020 at 1:04:50 PM UTC-4, Fox\'s Mercantile wrote:
On 9/1/20 11:19 AM, Michael_A_Terrell wrote:
Let me know if that doesn\'t pan out.
I am sending Peter a Blonder Tongue Agile Modulator.
Model: AM 40-450 Stock No. 59406.
Complete with a manual for setting the output channel
dip switches.



Nice. It would appear that you are not the prick most people in other hemispheres would have us believe.

Many many moons ago when cable TV was still analog, I put an A/B switch on the main line of my cable and used the B side to feed my distribution amp in which the output was connected to a set of rabbit ears and the A side to feed the cable box. That setup broadcast the whole VHF spectrum to any TV in the shop I would put a clip lead to. One day the cable guy comes in - they had been driving around \"sniffing\" for leakage, and my store was a real hotspot. He thought I had an open ground, but I told him I knew where the bad crimp was and threw the switch to A and the problem went away. The next day I went back to using the B side and a couple of months later they came in again, so they must have sniffed routinely , so I abandoned the plan. I should have tried broadcasting the output of the box alone - maybe they wouldn\'t have bothered me if it was a narrow spectrum.
That stunt could have wiped out communications for emergency
vehicles on the VHF high band, the two meter ham band and airports. You
could have indirectly caused people to die.

Well, that might explain the several near misses of aircraft at 15000ft over our city... FFS, do you honestly think a milliwatt output into a pair of rabbit ears with a range of about 15 - 20 feet would end emergency communications and civilization as well? I have a feeling your broadcast \"career\" was wiring up TVs for Chucky Cheese - and you were paid in pizza and Sprite..

 

[Michael_A_Terrell]

ohg...@gmail.com wrote:

On Tuesday, September 1, 2020 at 4:29:43 PM UTC-4, terrell....@gmail.com wrote:
ohg...@gmail.com wrote:
On Tuesday, September 1, 2020 at 1:04:50 PM UTC-4, Fox\'s Mercantile wrote:
On 9/1/20 11:19 AM, Michael_A_Terrell wrote:
Let me know if that doesn\'t pan out.
I am sending Peter a Blonder Tongue Agile Modulator.
Model: AM 40-450 Stock No. 59406.
Complete with a manual for setting the output channel
dip switches.



Nice. It would appear that you are not the prick most people in other hemispheres would have us believe.

Many many moons ago when cable TV was still analog, I put an A/B switch on the main line of my cable and used the B side to feed my distribution amp in which the output was connected to a set of rabbit ears and the A side to feed the cable box. That setup broadcast the whole VHF spectrum to any TV in the shop I would put a clip lead to. One day the cable guy comes in - they had been driving around \"sniffing\" for leakage, and my store was a real hotspot. He thought I had an open ground, but I told him I knew where the bad crimp was and threw the switch to A and the problem went away. The next day I went back to using the B side and a couple of months later they came in again, so they must have sniffed routinely , so I abandoned the plan. I should have tried broadcasting the output of the box alone - maybe they wouldn\'t have bothered me if it was a narrow spectrum.
That stunt could have wiped out communications for emergency
vehicles on the VHF high band, the two meter ham band and airports. You
could have indirectly caused people to die.

Well, that might explain the several near misses of aircraft at 15000ft over our city... FFS, do you honestly think a milliwatt output into a pair of rabbit ears with a range of about 15 - 20 feet would end emergency communications and civilization as well? I have a feeling your broadcast \"career\" was wiring up TVs for Chucky Cheese - and you were paid in pizza and Sprite..

Sigh. I was a broadcast engineer for AFRTS in the \'70s while I was in
the US Army. I have the distinction of being the only one to ever test
out of the three year 26T20 school while in Basic. It was a combination
of Electrical Engineering, and Broadcast Engineering. My score was over
90%, the average score was 20%. I also have a letter of Commendation
from a two star general for the job I did, rebuilding the station at Ft.
Greely, Alaska. I worked for Weathervision, at Ft. Rucker. We provided
two channels of weather data for the flight school, along with ten
channels of ETV for the flight school and Infantry school. We built one
of the first remote switching for the civilian cable TV that served the
base. A custom, high isolation RF switch was connected were it entered
the base. At the flip of a switch in th ETV building took it over, and
all 12 channels carried the same information. It was only used during
emergencies. It was powered through a dedicated pair provided by our
telecommunications section.

Later on, I worked for WACX in Orlando, Florida. We were on Ch 55,
with a 5MW EIRP from a 1700 foot tower.

After that, I was the \'Engineer of Record\' when I built WMRX under
the FCC construction permit, in Destin Florida. It was on Ch 58.

Aircraft used AM radio with a sensitivity in the singe digit
microvolt levels. If we could detect the leakage from blocks away, it is
radiating more than you think. The system I worked for in Cincinnati,
Ohio provided +10dBmv for each drop. You do the math.

When you have more than one idiot doing intention leakage, it adds
up to enough radiation to cause problems. Some cable channels were not
allowed to be used near airports, because of this. What you think,
doesn\'t really matter. It is what the FCC requires. If they drive one of
their monitoring vans through your service area and detect leakage, the
cable system is fined.

I\'ve never been in a Chucky Cheese. Enjoy playing with the other
children, when you\'re there.


--
Never piss off an Engineer!

They don\'t get mad.

They don\'t get even.

They go for over unity! ;-)

 

[Fox\'s Mercantile]

On 9/6/20 12:56 AM, Michael_A_Terrell wrote:
> [ Another boring bit of \"look at me!\" ]

I\'d mention what I did in the 25 years I spent in the aerospace
industry, but I don\'t need to brag to get an erection.

Those that know me, know what I did.



--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Michael_A_Terrell]

Fox\'s Mercantile wrote:

On 9/6/20 12:56 AM, Michael_A_Terrell wrote:
[ Another boring bit of \"look at me!\" ]

I\'d mention what I did in the 25 years I spent in the aerospace
industry, but I don\'t need to brag to get an erection.

Those that know me, know what I did.

Yes. You just bragged about not bragging.


--
Never piss off an Engineer!

They don\'t get mad.

They don\'t get even.

They go for over unity! ;-)

 

[Fox\'s Mercantile]

On 9/7/20 11:23 AM, Michael_A_Terrell wrote:

Fox\'s Mercantile wrote:
On 9/6/20 12:56 AM, Michael_A_Terrell wrote:
[ Another boring bit of \"look at me!\" ]

I\'d mention what I did in the 25 years I spent in the aerospace
industry, but I don\'t need to brag to get an erection.

Those that know me, know what I did.


   Yes. You just bragged about not bragging.

Yeah, fancy that.
And without several pages of \"I did I did I did.\"


--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[ohg...@gmail.com]

On Sunday, September 6, 2020 at 1:56:35 AM UTC-4, terrell....@gmail.com wrote:

I\'ve never been in a Chucky Cheese.

That actually is the one thing you\'ve said so far that doesn\'t smack of bullshit. Visiting a Chucky Cheese would mean you would have had children or grandchildren to dote over. Since no woman on the planet would voluntarily procreate with you, there would be no reason for you to visit any place kids love unless you are also a perv (I will however give you the benefit of the doubt on this at least). It also means your line of defective genetics will end with your demise.

Fortunately.

{get ready for the big stinking pile of bullshit about how he has 10 kids - all doctors, lawyers, scientists, or Senators and all Ive League graduates....}

 

[Michael_A_Terrell]

ohg...@gmail.com wrote:

On Sunday, September 6, 2020 at 1:56:35 AM UTC-4, terrell....@gmail.com wrote:



I\'ve never been in a Chucky Cheese.

That actually is the one thing you\'ve said so far that doesn\'t smack of bullshit. Visiting a Chucky Cheese would mean you would have had children or grandchildren to dote over. Since no woman on the planet would voluntarily procreate with you, there would be no reason for you to visit any place kids love unless you are also a perv (I will however give you the benefit of the doubt on this at least). It also means your line of defective genetics will end with your demise.

Fortunately.

{get ready for the big stinking pile of bullshit about how he has 10 kids - all doctors, lawyers, scientists, or Senators and all Ive League graduates...}

Yawn. BTW, it the \'Ivy League\' I don\'t really give a damn what you think.


--
Never piss off an Engineer!

They don\'t get mad.

They don\'t get even.

They go for over unity! ;-)

 

[ohg...@gmail.com]

On Monday, September 7, 2020 at 10:48:50 PM UTC-4, terrell....@gmail.com wrote:

ohg...@gmail.com wrote:
On Sunday, September 6, 2020 at 1:56:35 AM UTC-4, terrell....@gmail.com wrote:



I\'ve never been in a Chucky Cheese.

That actually is the one thing you\'ve said so far that doesn\'t smack of bullshit. Visiting a Chucky Cheese would mean you would have had children or grandchildren to dote over. Since no woman on the planet would voluntarily procreate with you, there would be no reason for you to visit any place kids love unless you are also a perv (I will however give you the benefit of the doubt on this at least). It also means your line of defective genetics will end with your demise.

Fortunately.

{get ready for the big stinking pile of bullshit about how he has 10 kids - all doctors, lawyers, scientists, or Senators and all Ive League graduates...}

Yawn. BTW, it the \'Ivy League\'

BTW, it\'s \"it\'s\", not \"it\". Contractions. Learn them, known them, love them.

 

[Fox\'s Mercantile]

On 9/8/20 5:56 AM, ohg...@gmail.com wrote:

Yawn. BTW, it the \'Ivy League\'

BTW, it\'s \"it\'s\", not \"it\". Contractions. Learn them, known them,
love them.

Note: If you\'re going to be a grammar Nazi, make sure your boots are
polished.


--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[pfjw@aol.com]

The favorite Go-To of the grammatically ignorant is: \"But you know what I mean.\"

No, I do not know what you mean, I know what you said (wrote). I am still trying to discern what you mean.

Peter Wieck
Melrose Park, PA