Chinese BJ300 Linear Amplifier =500wPEP

[@James-l4v4i]

The BJ-300 will do 300 watts peak, at most, and you're lucky if one will do that. Either you are reading the meter wrong or it's very inaccurate.

[@JimCoupeTQ]

Hmm i dont understand.. You are pushing 50W into it?? That would burn it or am I lost here? it says 2-10W input?

[@truth4grace580]

I have two of these bad boys, and I definitely get out. They say you can run up to 10w dead key into them but I only go 4w and they don't even get warm. Great budget amps!

[@icemansify]

I run one in my car with a 5' Sirio twin log antenna and have made contacts over 8000km, it out performs the Zetagi I paid over $700 for. I will buy another as a spare... Great value.

[@truth4grace580]

@@icemansify I'm currently running a Galaxy Saturn base station from the 1980s and a tram 1498 base antenna with this amp, I talked coast to coast from California to New York, Florida, Hawaii, Mexico, Jamaica, and Australia. It definitely gets the job done.

[@franciscolopez3229]

Good for you guys. Mine is kinda wonky, at 3 watts deadkey, mine pinches off and I see it in the meter moving in reverse instead of moving forward. In SSB, no problem at all.

[@truth4grace580]

@@franciscolopez3229 I had that same problem with my Cobra 25. Still haven't figured it out.

[@franciscolopez3229]

@@truth4grace580 Well, most of this kind of amps from what I've learned would run ok on AM wirh just around 1 to 1.5 watts deadkey and they should be fine.

[@HarishKottayam]

Hi, I am experiencing a spike in swr while transmitting... Any suggestions on patch cable length connecting the amp with rig.. using a xiegu g90 with bj300...

[@murraypirt6149]

My hi and lo power switch positions seems reversed as well

[@bobcraw1582]

Hi got one of these from Alibaba, got it all set up and looking good, set the radio to 5watts pressed the key on the mic high SWR on the radio, and did everything to get the SWR down. Oh yes, the radio is the new Anytone6666 Pro. Does anyone have any idea what is wrong

[@Dan-hx9og]

Get a low pass filter that will take care of the high SWR’s

[@georgegetterdone896]

What size power supply being used would a 30 amp supply I noticed Amazon us is selling that model at 125$ calling it " family" they also have the 200 model at 98$ supposedly only 50 watt out you would think the math would put the output at 300-200 for the 200 model if the 300 model does just 500

[@vsmichael1]

That amp will never do 500. Hold a constant audiooooooo on it & watch the meter drop. You are seeing the forward momentum of the needle & you unkey so fast you aren’t letting the needle come to a resting point. Say audio for 5 seconds or more & see what it’s doing. If you have a SWR 1.5 up you will get reflect back into the amp showing more power than it’s really doing. That amp has 2xsd1446 & they are 70 watts each. Lucky to see 200 pep.

[@LeeWhiting-k3x]

Exactly correct. Lucky to see 200 pep. Use a Bird 43P or better yet a Telepost LP-100A to see true PEP. You will be lucky to see 200PEP

[@JamminJerseyRocker]

Spot On! These amps are terrible except to make the power meter move. I bought 2 and I'm dumping both of them! Noise at dead key, garbled modulation, screws up the SWR and reflects back about 6 watts. 3-4 watts in put 160 watts out of nothing but frustration! 400 watts, NO WAY!

[@kieran-299]

The meter reads 100 watts ,not 500 dummy, its the scale beneath the top scale for 1000max scale. This amp model puts out about max of 150 w AM, and about 300w SSB thats WHY its model # is 300. Your meter read about 5 w Input,so you dont know how to correctly read the meters.

[@manqueensg4mbit250]

what is input power requirement for BJ300 ?

[@franciscolopez3229]

1 to 5 watts on AM & FM, and 5 to 10 watts P.E.P. on SSB.

[@dougc.1773]

You're not accounting for ballistic meter over-shoot.

[@vsmichael1]

Correct, forward momentum of the meter & he is unkeying to quick.

[@henryguitron4837]

I bought one and it doesn't work on high power all my radios have d104s power mics and it just squeals like a pig and I'm only driving it with 4 watts swr is 1.2 been on the radio over 30 years and never had a problem with amps this one is no good for me.

[@RT038]

Trying using a sadelta desk mic it won't squel I had the same problem with hand held power microphones you don't get that amount of power out of the bj300 just over 100watts I burnt mind out running a crappy cheap power supply you need at least 15amps to run this no issue

[@RT038]

Squeal spelt it wrong

[@worldradio520]

How is it doing 500w when they are only rated for 300w max sideband

[@worldradio520]

Ah i see now you are using that bigger amp beside that little one isnt even hooked up 😂

[@louisdalessandro2495]

Mine back dips at a 3 1/2 watt dead key and puts out 175 watts ,gonna lower dead key to 1 or 2 watts

[@franciscolopez3229]

Same here at only 3 watts deadkey. But on SSB, it works great.

[@Gw0wvl]

50 watts 🤣 ... From a pair of 75 watt transistors .... The maths doesn't add up .

[@icemansify]

Neither does your comment 😂🤣😂🤣The meter doesn't lie,

[@kontikinomads6750]

Agreed simple math says impossible however he got a workman meter😂😂

[@louisdalessandro2495]

75 watts is at 12 amps 125 watts is more like it per transistor at 13.5 amps

[@arconeagain]

​​@@icemansify you trust that ultra expensive measuring instrument, as instruments never lie. That's why planes stay in the sky, and large companies would never spend hundreds of thousands of dollars, if not millions of $ for their equipment. Atomic clock? Atomic whatti? Calibrate/check against another meter? Never. I take everything as gospel, especially when it's made from the finest (think about it) components in China. I mean, their porcelain used to be fine, cutting edge.

[@kylefreemason]

Are these rf sensing?

[@crazyham]

Yes, They trigger with the RF and don't need a trigger cable.

[@arconeagain]

That Workman meter really works for ya, ay.

[@crazyham]

Did you remove my Comment ? I was simply being helpful and giving a realistic opinion. When a Wave has a sudden edge, (Not a sine) more energy is created but for a short time, and that is why it probably seems like 500 watt to your meter. It would not be doing 500 watt average but it is still great for getting a peaky signal out there. Tesla used impulse electricity for that reason.

[@ericzerkle8486]

You hams tend to come off to most people as rather annoying.

[@JustinRuth-km4wz]

Your only making 100 watts average .man ,not 500 ...that thing will never make 500 average ..your insane

[@mauroossidi9298]

non ha nessun filtro in uscita nemmeno un misero passa basso a 30 Mhz, la potenza misurata non e' quella reale ma la somma di spurie armoniche, soprattutto quelle dispari perche' lavora in classe C, oltretutto il cavo rossonero e' cosi' piccolo che al finale arriveranno non piu' di 10/11 volt

[@bubbleslahey8459]

They will do a couple of hundred easy but check your radios s.w.r. not your meter and you will bin it....pure shite!, ,