Suggestions for a 100 Watt Class amplifier for a FLEX-1500?

[AB2YC]

Well I broke down and just ordered an amp since the more I looked at this it
was not cost effective since I still would have needed to get a 6 meter amp

I wound up getting the HL-45B since it has 6 meters.

Thanks all for the suggestions, it was just not cost effective in the end.

[WB2WIK]

The HL-45B is a very good amp, but not 100W, I guess it's really about 45-50W.

I had one in the motor home for use with an FT-817 for years and it never failed.

Good luck!

(BTW the Ten Tec amp isn't a bad deal: It's more power than the THP amp and has some additional features, for not a lot more money.  However, I don't have one so can't comment on how well it works.)

[AB2YC]

The HL-45B is a very good amp, but not 100W, I guess it's really about 45-50W.

I had one in the motor home for use with an FT-817 for years and it never failed.

Good luck!

(BTW the Ten Tec amp isn't a bad deal: It's more power than the THP amp and has some additional features, for not a lot more money.  However, I don't have one so can't comment on how well it works.)

I would have liked 100 watts but 45 is only about a half an s unit lower.
The TenTec looks nice but was more than I wanted to spend now.

From what I have been reading the HL-45B seems like a good amp.

Thank you

[N6AJR]

sell the 1500 and get a 100 watt radio.  for about the same price, you can get one of the origonal sdr rigs , a ten tec pegasus

[ZENKI]

This is the real problem with all this QRP brainwashing. Work the world on 5 watts its easy  as using a telephone NOT!

All the QRP radios like the FT817, Flex, IC703 and other  that are sold end up with  some sort of amplifier down the track. 9 times out of 10 its a crap CB amp  or some cheap  CB copy kit amp.
These AMPS have horrendous IMD performance because of low battery voltage and uncompensated bias systems. The result on the air is disaster. I have heard all these crummy signals from these stations on the air
and the resulting signal is terrible.

Why anyone would want to put up with a tiny radio, external amp and all the wiring mess when you can buy a decent radio like FT857, TS50 or IC706 is  hard to understand.  Even in the Flexradios case buying a Flex3000 would have made more sense if the SDR platform is your preferred choice. I guess some people just like doing things the hard way.

From a technical perspective adding using a transceiver with a marginal amp and the resultant IMD is always worst than the  radios IMD by itself. Nobody figures this fact into  their buy a cheap amp for my QRP radio act.

At the end of the day using these QRP radios has no real power consumption benefits because all these radios are current hogs on receive.  You might as well just use a 100 watt normal radio.

I dont know why Flexradio cant design a clean decent amplifier for their products. I see active promotion of RM Italy CB class C products on the Flexradio reflector, just another reflection of their poor technical knowledge.
Now I read  another post on the Elecraft reflector. Another joker promoting his poor IMD Flex1500  and using it with a trashy splattering RM CB amplifier. I guess the moderators on Elecraft are going easy on all the new KX3 owners who
will be doing the same.  The worlds best QRP radio will be used with the worlds worst CB amps and the who cares if the crud kills your new 10,000 dollar  receiver.  Ignorance is bliss!

sell the 1500 and get a 100 watt radio.  for about the same price, you can get one of the origonal sdr rigs , a ten tec pegasus

[KE5JPP]

sell the 1500 and get a 100 watt radio.  for about the same price, you can get one of the origonal sdr rigs , a ten tec pegasus

I would not consider a TEN TEC Pegasus to be a SDR (no more than the Jupiter is a SDR).  It is a computer controlled radio.

[KE5JPP]

I dont know why Flexradio cant design a clean decent amplifier for their products. I see active promotion of RM Italy CB class C products on the Flexradio reflector, just another reflection of their poor technical knowledge.
Now I read  another post on the Elecraft reflector. Another joker promoting his poor IMD Flex1500  and using it with a trashy splattering RM CB amplifier. I guess the moderators on Elecraft are going easy on all the new KX3 owners who
will be doing the same.  The worlds best QRP radio will be used with the worlds worst CB amps and the who cares if the crud kills your new 10,000 dollar  receiver.  Ignorance is bliss!

Flex can't even put a decent PA in its top of the line $8000 radio.  If they did not do it with that, they never will.  This shows their technical incompetence.  All the high performance receivers in the world won't be worth a crap with all the splattering transmitters and amps out there.  Heck, you might as well not spend much more on the receiver than what the lowly $500 Alinco HF rig costs - at least you'll have 100 watts.

[WD5GWY]

I think the above comment was uncalled for. No need for foul
language. 
 While you may not agree with him, there's no need for such
a comment like that.
james
WD5GWY

[KE5JPP]

I think the above comment was uncalled for. No need for foul
language. 
 While you may not agree with him, there's no need for such
a comment like that.
james
WD5GWY

Looks like eHam removed the post.  I agree though - such foul language was uncalled for from "RFDOG".  If you look at his posts they are all like that.  I am surprised that eHam has not kicked him off the forums yet.  Clearly he is an anonymous coward.

[WD5GWY]

I think the above comment was uncalled for. No need for foul
language. 
 While you may not agree with him, there's no need for such
a comment like that.
james
WD5GWY

Looks like eHam removed the post.  I agree though - such foul language was uncalled for from "RFDOG".  If you look at his posts they are all like that.  I am surprised that eHam has not kicked him off the forums yet.  Clearly he is an anonymous coward.

Well, as you once told me, it's one thing to argue a point with someone, but quite
another to insult someone. And that type of language isn't necessary to make a point.
james
WD5GWY

[K3GM]

At the risk of repeating myself.....ah what the heck:
The ARRL lab measured 3rd order IM products on TX of -22dB on 40m @ full output (5W).  If you take the output of the 1500 and boost it 13 dB by running it into an amplifier, any amplifier, you will end up with spurs of considerable power inside the operating band.  That example is assuming the amplifier doesn't introduce any IMD of its own, and if you can show me one of those, I'll buy it.  The laws of physics are irrefutable: Even order IMD products typically fall outside the band and can/could be filtered out by a following PA.  Odd order IMD products typically fall inside the operating band and thus cannot be filtered out by any PA.

The is no amplifier...repeat NO amplifier commercial or home brew that is capable of filtering the 3rd order IMD products generated by the 1500 because they fall within the band you're operating in. If you drive a typical 100 watt amplifier with a Flex 1500, third order IMD can be down as little as-9db from your transmitted signal.

The Flex 1500 is an interesting QRP transceiver.  Let it remain that.

[AB2YC]

I wound up getting the HL-45B amp (45 watts), Though maybe I should have held off.
The 5 watts from the Flex-1500 actually does pretty good all by itself.





 

[KW6LA]

I agree with K6AER- The HLA-300 amplifier  is very good value and if driven properly clean enough to make Zenki Happy.  Not all of their products are, so one must use their best
judgment when buying and operating one.   

[WD5GWY]

I wound up getting the HL-45B amp (45 watts), Though maybe I should have held off.
The 5 watts from the Flex-1500 actually does pretty good all by itself.





 

The Tokyo Highpower HL-45B is a nice amp. I have a friend that uses one.
It is surprising how well the 1500 does, even at 5 watts. I use mine regularly
and have had very few people say they had a hard time hearing me.
It's certainly not 20 over 9, but, then again, if you can carry on a conversation
without a lot of repeats, then things are not that bad.
Have fun, the 1500 is a very good qrp rig and priced just right.
james
WD5GWY

[WV4I]

Here using RM Italy HLA 150 amp with Flex 1500. At less than 5 watts from Flex, lights all led s on amp and on LDG AT 200Pro tuner (latter max 250W). Works great. No adverse reports.