Subject: Ameritron AL-1200 I did a lot of research before choosing a new amplifier, and so far I'm very pleased with my choice: the Ameritron AL-1200 ($1650 at Texas Towers, $1699 at HRO). This is a great amplifier. It uses the Eimac 3CX1200A7 tube, which means the AL-1200 has a number of advantages over the 3CX800-based amps (Alpha 86,86A,87A, Titan 425, Commander Series, etc.): Feature AL-1200 3CX800-based amps -------------------- -------------------- -------------------------- 1. Warm-up period Instant On 3-minute warm-up mandatory 2. Grid Dissipation 50 watts 4 watts 3. Drive req'd (1500W) 100 watts 65 watts (forgiving) (unforgiving) 4. Protection circuits Power supply Fuses plus many tube protection fuses trip-off circuits mandatory 5. QSK N/A until new Vacuum Relays (noisy). PIN-5 board avail. Alpha uses a failure-prone (45 days from now) PIN diode scheme with known 160-meter problems. 6. Construction Pretty good, a bit Varies. Alpha construction old-fashioned (e.g., is very clean and professional. some terminal strips). 7. Cabinet Rather large Moderate to small 8. Price Texas Towers $1650 $2000-$3600 HRO $1699 9. Reliability Good reputation Fair reputation 10. Metering Large, backlit, LED wattmeter and tune circuit needles. Wattmeter in the Alpha allows for is not accurate. adjustment while operating. 11. Fan Noise Moderately high. Alpha has high/low toggle For light use, fan switch on back panel. speed may be reduced by movng some wires on a terminal strip. 12. Knobs Very smooth vernier Alpha feels a bit mushier. tuning, with a red Titan has vernier control, needle that moves. but coarse markings. 13. RTTY Not a good RTTY amp. No time limit key down Maximum key down in some models. time at full power: 15-30 seconds on 10/15. Longer on lower bands. High-Q tank coils may overheat if you try. We used my AL-1200 for 48 hours in the CQ WW SSB. It worked flawlessly until the last 5 minutes of the contest when the operator accidentally loaded up the amp. on 20 meters when the exciter was still on 15 meters. A simple 15 amp. glass fuse in the power supply blew. Replaced fuse (easy access from rear), and AL-1200 seems to be just fine. The AL-1200 is very forgiving during tuneup unlike most 3CX800-based amps. Due to high SWR in the phone band, I didn't always have time to retune the amp. It never complained. I could never do that with a 3CX800-based amp. The only other 3CX1200A7 based amp. I know of is the Henry 3KD Premiere. A friend has had a lot of problems with his, mostly due to poor mechanical construction inside (plastic cams, gears, and chains for bandswitching; "homebrew" parts inside). I do not recommend any of the newer Henry amps. They don't seem to build them like they used to, and the manuals are terrible. Haven't heard a bad report yet from an AL-1200 owner. 73, Bob, N6TV Additional Info: The AL-1200 has a high Q Pi-L output tank circuit. The 12V T/R relay seems big enough. At first, I couldn't even get it to close (the transistor T/R switch in the TS-930 couldn't draw enough current to cause closure of the amp. relay.) Now it works fine: a relay in the TS-930 closes the relay in the AL-1200. I've never heard the relay arc or make any funny noises. It seems big enough to handle the job. It uses a heavy Peter Dahl transformer (I think it's Hypersil), which you install yourself. Power supply doesn't make any humming, buzzing, or whining noises when key down. (Ever listen to a Henry 2K hum along with your CW? You can copy code just by listening to the amp!) On the AL-1200, the plate voltage runs about 3600V key up and 3300V key down. The SSB/CW switch changes the bias, not the plate voltage. 73, Bob, N6TV I've used and abused my AL-1200 for about four years now with no problems at all. The worst that ever happened was to load it into about a 4:1 SWR at about 3 AM. There was a bit of arcing on the loading cap. There was no apparent physical damage. That was about three years ago. I have no problem recommending it. 73 Gene WA2UKA Subject: AMERITRON AL-1200 I too used an AL-1200 for this past weekend's CQWW contest. This was the first contest I've used it in. Previously I had an AL-1500 which uses an 8877 with the 3 minute warm-up, low drive requirement, etc. After going through 4 tubes under warranty over a 3 year period, I dumped the amp and am now using the much more rugged 3CX1200A7 in the AL-1200. I cannot say enough about how pleased I am with the AL-1200. Running a full 1500 out on 15 all weekend was no problem. The amp got very warm, which is normal for the 3CX1200A7. I would not say it got "hot". I could always place my hand on the cabinet over the tube without too much discomfort. Based on Gene's, WA2UKA, experience with the AL-1200 I made the change and am glad I did. I do have the most recent version of the Pin 5 QSK board installed which I purchased through AES in the Midwest. If you can find a distributor with any stock I would recommend the unit. Ameritron told me a newer unit was under development, but the reduced switching time didn't seem worth the wait...or the likely increase in price! The AL-1200 has my vote.....73, NG2X Brad Petersen