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Varmit 1000
- Thread starter King Mudduck
- Start date
Remember: GI=GO (Garbage IN equals Garbage OUT), if you have one of those wildly swinging radios then, you are going to get "Splatter".
Back in the "Ol Days" (when that Varmint was built), a radio did 4 watts and, on an Oscilloscope (not a watt-meter) you could see 16 watts out of a fully modulated (100%) signal. I specified "O-Scope" because it has the ability to capture and measure the amplitude of the signal referenced to a certain period of time. A typical watt-meter is just measuring the voltage drop across a resistor which causes a meter movement to deflect. A "typical" watt-meter is not capable of displaying the true power from a RF circuit.
I also stated, "fully modulated" signal; "100% Modulation" is a reference to the amount of bandwidth that your transmitted signal occupies. This means that if the center frequency is 27.025 Mhz and your transmitted signal is confined to 3 Kc above and below the center frequency (6 Kc total) then, you have 100% modulation. Take up more that 6 Kilo-cycles and you have over "100%" modulation. Modulation is not measured by how far you can deflect a watt-meter.
Because the AM detector in your radio deciphers the information from the RF signal based on how and how much the signal varies from a zero reference point, someone figured out that if *I* make the percentage of change from 0 to "whatever" greater, the output will be louder in the receiver. This is achieved by lowering the dead key and making the radio swing higher; the percentage of change just makes those AM detectors go crazy.
Now, to answer your original question: Brewer Labs, the builder of the Varmit series incorperated a low-pass filter in their design, it looks like this:
This filter may or may not still be in your set, pop the hood and take a look but, that filter will not help you against a bad signal in.
.
Back in the "Ol Days" (when that Varmint was built), a radio did 4 watts and, on an Oscilloscope (not a watt-meter) you could see 16 watts out of a fully modulated (100%) signal. I specified "O-Scope" because it has the ability to capture and measure the amplitude of the signal referenced to a certain period of time. A typical watt-meter is just measuring the voltage drop across a resistor which causes a meter movement to deflect. A "typical" watt-meter is not capable of displaying the true power from a RF circuit.
I also stated, "fully modulated" signal; "100% Modulation" is a reference to the amount of bandwidth that your transmitted signal occupies. This means that if the center frequency is 27.025 Mhz and your transmitted signal is confined to 3 Kc above and below the center frequency (6 Kc total) then, you have 100% modulation. Take up more that 6 Kilo-cycles and you have over "100%" modulation. Modulation is not measured by how far you can deflect a watt-meter.
Because the AM detector in your radio deciphers the information from the RF signal based on how and how much the signal varies from a zero reference point, someone figured out that if *I* make the percentage of change from 0 to "whatever" greater, the output will be louder in the receiver. This is achieved by lowering the dead key and making the radio swing higher; the percentage of change just makes those AM detectors go crazy.
Now, to answer your original question: Brewer Labs, the builder of the Varmit series incorperated a low-pass filter in their design, it looks like this:
This filter may or may not still be in your set, pop the hood and take a look but, that filter will not help you against a bad signal in.
.
Thanks Paws. I run a clean setup with nothing clipped and none of the 1 watt swinging to whatever crap! May try it out just to see how it does.
paws264 said:
Sorry paws but that is soooo not correct.Transmitted bandwidth and % of modulation have nothing in common.You can be 2 KHz wide and 100% modulation or you can be 10 KHz wide and 2% modulation if the passband of the radio will allow it.Bandwidth is a function of the frequency of the audio signal fed to the modulator while % modulation is a function of what level that audio signal is.Now on the other hand a radio with more than 100% modulation will occupy more bandwidth but that is because of the crap generated by the hard switching off and on of the carrier every time voice peaks exceed 100% negative modulation.I suspect that is what you meant.No?
Hmmm well I will state the obvious that no one else wants to mention.
So you want to run a grand on CB and not bleed over on other channels ??
Forgeddaboudit
That much power....you are going to be a bleeder. Keeping your modulation under control will (help) but shucks....having a KW and running 50% modulation is no fun. Everyone will tell you you're sounding soft and need more. Heck if you want to be loud and clear....and everyone does want to be loud and clear on AM CB....then go ahead and be loud and clear. But you're going to wipe everyone away in the neighborhood on other channels simply due to the sheer force of your huge signal output.
If you don't want to be a big bleeder, then don't run a thousand watts. It's the elephant standing in the room.
Good luck
So you want to run a grand on CB and not bleed over on other channels ??
Forgeddaboudit
That much power....you are going to be a bleeder. Keeping your modulation under control will (help) but shucks....having a KW and running 50% modulation is no fun. Everyone will tell you you're sounding soft and need more. Heck if you want to be loud and clear....and everyone does want to be loud and clear on AM CB....then go ahead and be loud and clear. But you're going to wipe everyone away in the neighborhood on other channels simply due to the sheer force of your huge signal output.
If you don't want to be a big bleeder, then don't run a thousand watts. It's the elephant standing in the room.
Good luck
this amp does not require alot of drive or pep to run it
if you have to much deadkey and to much pep then you are overloading it and causing it to splatter.
anything from 2 watt to 3 watt deadkey pep to 12 to 18 watts for drive
is ok anymore is to much nad running a export radio wont help either
i have 4 varmints 1 of what you speak of and a cobra 29 and 2 golden eagles
i can use any of the varmints as a driver for the sb-220s and no splatter
now i can take the 2517 or the s-3 and i catch some lines and scratching.
now run either them 2 radios into a 1x4 on the base and the neighborhood comes alive
but back to the trash in will get even more trash out
Remember: GI=GO (Garbage IN equals Garbage OUT), if you have one of those wildly swinging radios then, you are going to get "Splatter".
Back in the "Ol Days" (when that Varmint was built), a radio did 4 watts and, on an Oscilloscope (not a watt-meter) you could see 16 watts out of a fully modulated (100%) signal. I specified "O-Scope" because it has the ability to capture and measure the amplitude of the signal referenced to a certain period of time. A typical watt-meter is just measuring the voltage drop across a resistor which causes a meter movement to deflect. A "typical" watt-meter is not capable of displaying the true power from a RF circuit.
I also stated, "fully modulated" signal; "100% Modulation" is a reference to the amount of bandwidth that your transmitted signal occupies. This means that if the center frequency is 27.025 Mhz and your transmitted signal is confined to 3 Kc above and below the center frequency (6 Kc total) then, you have 100% modulation. Take up more that 6 Kilo-cycles and you have over "100%" modulation. Modulation is not measured by how far you can deflect a watt-meter.
Because the AM detector in your radio deciphers the information from the RF signal based on how and how much the signal varies from a zero reference point, someone figured out that if *I* make the percentage of change from 0 to "whatever" greater, the output will be louder in the receiver. This is achieved by lowering the dead key and making the radio swing higher; the percentage of change just makes those AM detectors go crazy.
Now, to answer your original question: Brewer Labs, the builder of the Varmit series incorperated a low-pass filter in their design, it looks like this:
This filter may or may not still be in your set, pop the hood and take a look but, that filter will not help you against a bad signal in.
.
11/10/09
.
LOL, this is simply NOT true, true of most CB Amps, but running a Kilowatt out does NOT automatically meet your definition....
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