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low output from this 4 pill

There's all kinds of mischief and bullshit going on with meter readings on various people's YouTube channels. You can make a meter read pretty much whatever you want by adjusting it internally.
Also due to the lack of an LPF, those 400 watts includes all the radiation on harmonic frequencies. 400 watt reading DOESN'T mean 400 watts is radiating on the fundamental frequency.
 
They all have their good and bad points.
Donkeystomper seems to be one of the few willing to tell the truth on wattage claims. No he's not as polished as some of the other builders but in my opinion (which is worth the price you paid for it) he's telling the truth. He put out a a couple good videos on the subject.

One of a couple of em.

 
There's all kinds of mischief and bullshit going on with meter readings on various people's YouTube channels. You can make a meter read pretty much whatever you want by adjusting it internally.
Also due to the lack of an LPF, those 400 watts includes all the radiation on harmonic frequencies. 400 watt reading DOESN'T mean 400 watts is radiating on the fundamental frequency.
I am definitely going to look into a low, pass filter and look up how to solder it into what’s currently on the board, as far as wattage goes I’m not super anal about getting a shit ton of wattage out of this thing. I just know it is not working correctly, when my two pill swings just as much as the 4 pill on the same meter something has to be wrong? Right?
 
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when I tried ssb it would click like crazy cutting in and out.
That's because its a class C AM only amplifier.
Now some add an SSB delay capacitor to the relay circuit so the relay stops chattering but even doing that does not make it an SSB amplifier unless it has SSB biasing which is a whole new ball game, and unless you know what your doing to add THAT you could damage the pills.
That amp should do 400-450w PEP all day.

A low pass filter does not get soldered into the amp. There are not a lot of amp builders that incorporate a low pass filter inside the amp so don't worry about that.

A ground strap from the rear panel to the copper board is a good idea, thanks Brandon, as it does not have one.
 
Correct. It's should in theory output double what your two pill does, drive and condition / tune dependent. If you use a external LPF dont cheap out like I did.
Pay the money up front and get quality.
I failed at that and wound up replacing 4 pills when it (LPF) shorted out and took one of my pills out (had to replace all to ensure gain match).
 
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That's because its a class C AM only amplifier.
Now some add an SSB delay capacitor to the relay circuit so the relay stops chattering but even doing that does not make it an SSB amplifier unless it has SSB biasing which is a whole new ball game, and unless you know what your doing to add THAT you could damage the pills.
That amp should do 400-450w PEP all day.

A low pass filter does not get soldered into the amp. There are not a lot of amp builders that incorporate a low pass filter inside the amp so don't worry about that.

A ground strap from the rear panel to the copper board is a good idea, thanks Brandon, as it does not have one.
Got it, thanks for putting stuff in
Correct. It's should in theory output double what your two pill does, drive and condition / tune dependent. If you use a external LPF dont cheap out like I did.
Pay the money up front and get quality.
I failed at that and wound up replacing 4 pills when it (LPF) shorted out and took one of my pills out (had to replace all to ensure gain match)
Is there anyway to test the pills while they’re in the amp without any special tooling? Is there anyway to do a pulmonary check with a multimeter to see if they’re absolutely fried or not before using one of those pill testers tools ? I’m starting to think maybe I Arced something out when I was installing it and didn’t realize, maybe my eight gauge hotwire just grazed the heat sink, I am installing it in a single cab and don’t have much room to work to work So I can see that being a possibility.
 
In my limited knowledge, I do not beleive you can accurately test the pills gain while they are still in the amp. I could be wrong. More knowledgeable people will hopefully soon chime in.
 
Amp builders SHOULD all be incorporating low pass filters into their designs. It's cheap and irresponsible not to. RF amps for every other service, whether it's ham radio, broadcast radio, business band, or whatever, ALL have a low pass filter. It's considered a normal part of amp construction for everybody but builders of CB amps. And just because nobody else puts one in doesn't make it OK to not have one !

Fortunately they are cheap and available as an after market add on that goes between the amp output and the antenna. I know 429 had one short out (these things happen) but thousands of them are in daily use around the world without problems. I've used them for over 40 years without any problem ! They prevent interference to other radio users and services, which should be a huge plus as interference can lead to complaints which can lead to an FCC visit.

I'll also add that used ham gear is often cheaper than used CB stuff, can usually be modified for 11 meters, and ALWAYS includes a low pass filter.
 
I think my 2 pill palomar magnum has built in filters I will look at my next break.
It WOULD be interesting if one COULD add an internal one. I've not yet seen that done. But as BC states a quality filter could probably be sourced used fairly economically.
 
Correct. It's should in theory output double what your two pill does, drive and condition / tune dependent. If you use a external LPF dont cheap out like I did.
Pay the money up front and get quality.
I failed at that and wound up replacing 4 pills when it (LPF) shorted out and took one of my pills out (had to replace all to ensure gain match).
image.jpg

The guy who sold me the two pill a while back, gave me this with it I never used it.
 
Looks like a decent one but not rated for even a two pill really but yes a much larger version of that would be what you need. I took some photos of an internal one just for giggles and have a few of my repaired external one. I would NOT endorse this brand of external LPF clearly. But these are just as examples.
 

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That's an LPF all right ! That one is only rated at 100 watts maximum though, so while you could run it on your Lincoln barefoot, it won't help with the amp.
 
Woops. Meant to say 980, not Lincoln. And Lonestar is correct, you could use that on a two pill as well.
 
That's an LPF all right ! That one is only rated at 100 watts maximum though, so while you could run it on your Lincoln barefoot, it won't help with the amp.
image.jpg

OK things are starting to make sense, figures why I have never heard of a low pass filter when it comes to building an amp I had no clue it was an external thing, my only previous experience with low pass filter’s comes from the car audio world. Looks like I have a good bit of stuff to re-search, this fourm has probably been one of the most helpful forms I have ever posted to and I’m grateful that the Radio community doesn’t gate keep information like they do on other forums.
 
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Like BC says internal LPF in the CB community is rare. I usually buy any of those old blue heat sink magnum/skipper/cobra amps I run across as they do incorporate the filters. Not sure I've seen any other units built with them. Not terribly relevant to your amp, just informational regarding the internal filters.
20231106_131352.jpg
 
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