Is it time for amplifier mfgrs to step back and "rethink"

Discussion in 'Amateur Radio Amplifiers' started by KM5FL, Sep 6, 2011.

Thread Status:
Not open for further replies.
ad: L-HROutlet
ad: l-rl
ad: abrind-2
ad: Left-2
ad: Left-3
ad: Subscribe
ad: L-MFJ
  1. WB0LSR

    WB0LSR Ham Member QRZ Page

    You see what you see, I see a pointless and rather barbed opinion of a type of person obviously regarded with scorn by the poster. I see no need for that here in the technical forums, since frankly IMO there are enough "real ham" type arguments around here already. Different strokes for different folks I guess. I always try to base my assessment of someone on experience whenever possible, not speculation. That is the case here, nothing more. There is a reason why things like ignore lists are there. They are tools.

    I've already pointed out that we're off topic. I'll continue my participation here when we're back on topic. It has been a good discussion so far, and I agree with you about the importance of the advancement of technology. For me, there are applications for all different types of technology.. hell, I'm a musician and I love tube audio amps. The same mindset will no doubt apply to many radio folks about their tube amps. I understand that, but my reason for arguing in favor of silicon here is because there have been some very slick new developments in that regard recently that sort of change the game a bit.. again, IMO.
    Last edited: Sep 10, 2011
  2. AF6LJ

    AF6LJ Ham Member QRZ Page

    You are quite correct in pointing out the new devices available, I'm impressed with tham and have said so in another thread which you participated in.

    The best way to prove their ruggedness is for someone to build an HF amp using those devices and use the hell out of it, on different antennas and under different conditions. Someone has to be the first one.

    The trail blazers usually catch the most flack at first.
    Been there, done that, have the tee shirt.
  3. WB0LSR

    WB0LSR Ham Member QRZ Page

    You're absolutely right there.. N8ZRY recently built an LDMOS amplifier if I recall correctly.. but I can't seem to recall the details of the thread that I saw it in so I can't remember if it is HF or otherwise.
  4. NA0AA

    NA0AA Ham Member QRZ Page

    IF the quality of the components and cabinet was better than an AL-82, I'd pay a small premium for a Heathkit and still be glad to assemble myself - It would be one way to make sure it was properly built.
  5. KM1H

    KM1H Ham Member QRZ Page

    Thank you Sue, I appreciate the adult response. Ive done my share working at the leading edge at well over 100GHz in defense electronics but very little at high power SS HF.

  6. WA7KKP

    WA7KKP Ham Member QRZ Page

    I think you're meaning "re-invent the wheel" . . .

    Amplifier design is pretty much cut and dried depending on tubes, what's grounded and not, and class of operation. You want an amplifier with readily available tubes on a 'pull' basis (used but still have life). Broadcasting used to be the source for these, but most transmitters are now solid-state, except for the big tubes with 10k dissipation, far bigger than what we need. The filaments alone burn up over a kilowatt . . .

    Besides designing the amp, they have to go to the FCC and get type acceptance. Modify one part, and you start over again at square zero in this game of law. Parts available to handle the voltages and currents needed aren't cheap either, unless you buy surplus, or get an assembled amp for pennies on the dollar.

    CB radio manufacturers also play the type-acceptance thing; that's why many of the sideband models are still being made after 10-20 years of manufacture. The AM radio designs were forced into making them impossible to modify for out-of-band, and those are pretty much state-of-the-art. The older SSB designs are still quite easy to mod the PLL for out-of-band operation; now they just epoxy the chip/board to prevent prying fingers.

    I would like to see an amp without relays of any sort, using soft-start SCR control of the plate voltage (no thumps) and PIN diode switching for full QSK on CW or AMTOR. Not having that, I'll just have to build one to my own tastes.

    Gary WA7KKP
Thread Status:
Not open for further replies.

Share This Page