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not down to milliwatts. perhaps below a watt though not enough drive to keep class C pair of 2879 turned on sufficiently. Consider the basic fact that if less than 0.6v on the base a transistor is off. That means with a push-pull pair less than +/-0.6v on the output if the input transformer...

Class C amps will have input VSWR issues at low RF drive levels. The reason is that the pills are starting to shut off at reduced RF input drive, which makes the input appear to be de-tuning. With class C amps, its the "inertia" of the input/output transformers that fill in the gaps when both...

Significant improvement? Depends on what you're trying to improve. If your problem is TVI or the like, then the GPK is a big plus. Either that or an ugly balun coax choke. The antenna needs some kind of counter-poise. It'll use whatever metal is connected to it, coax shield or mast...

Internet Explorer is better because it can do this:

yes. those rigs were class C with only the final stage keyed for CW. They had no key click problems because the key line had a simple shaping network. However, if you key an exciter and then amplify it with a class C amp, then you can have key click problems with that.

Tuning up this preamp could be easier if they included a variable capacitor for the RF input C2. But for a $15 kit, i doubt that would be practical. i'm not sure if they use the 2SC2498 or the 2SC2570A, but the latter would be better due to lower noise. The best of the best preamps use...

Everything i read about CW and class C points to key clicks. The bandwidth of a CW signal depends on how fast the carrier power rises and falls. Could be that the non-linearity of a class C amp could cause key clicks due to the non-linearity changing the rise-fall keying shape.

On UHF you really need to pay attention to coax loss. Because RG8X has nearly 13dB loss for 100feet length on FRS/GMRS. You can see on the 450MHz row: Communications Coax Other item of concern when looking at ham antennas for GMRS in that ham antennas are only intended to run up to 450MHz...

This is a horizontal dipole? If so, it should be at least 1/2 wavelength above ground to get a useable radiation angle. you can get the details here Dipole Height

bob85: yes, another CB myth. Just like the 18 foot coax myth. Here is all the details of the bird element A Photo Tour of a Bird Wattmeter Element I doubt you'll find anyone coming onto this thread defending the claim that birds dont read CB harmonics.

It is not a stupid question. It is answered here Motor vehicle exception - Wikipedia, the free encyclopedia But the question would be whether radio equipment in a vehicle would qualify as contraband.

Really? the datasheet you link to shows 100 watt plate dissipation rating. But it does show that you get 200 watts out with a 2kv plate voltage. It shows half watt drive to get that. So if you hit a pair of those with 50 watts, its hasta lavista baby.

Its possible to build, but its just not practical. Linear supplies weigh on the order of one pound per amp. and thats probably on the light side. For alternative there is a switching power supply, but then your talking major $$ if you dont want RFI hash everywhere. This is why tube...

If you disconnect the coax from the CB, the noise is still there? i mean just only DC power going to CB.

I think NU9N got the overmodulated labels for low-level and high-level backwards. High-level is where modulation power is applied to the DC power of the final(s). Also known as "plate modulation". Low-level is where modulation is applied before the final amplifier and then amplified by...

A bird slug is basically just a pickup wire with a resistor on one side and a detector diode on the other. There are no frequency limiting components other than the pickup wire itself. When you operate a bird slug outside the frequency range printed on the front, the only thing you lose is...

I think the joke was about what frequency the swan users meet on. The answer was any frequency, because eventually they'll drift on by.

Ham Radio is a useful route to pursue, but you are looking for internet access for rural schools. You should know that 2.4GHz wifi is capable of long distances. High gain yagi antennas are readily available for wifi frequencies. In addition, there are so many choices of wireless mesh...

yes. people dont understand that the tokyo amp is a base station amp. Its only fair to compare it with other ham base amps. But the solid state amp from them is no-tune, meaning its just key up and talk. Also, about the texas star amps. People need to understand those amps are RF keyed...

this might be the place Singer Manuals from Vintage Manuals, Inc.