| OE3JTB |
Rating:     |
2004-09-06 | |
| Good job |
Time Owned: 0 to 3 months. |
I owned this pa for 2 months, my TRX is a Kenwood TS-570 DG.
As described below, the TS 570 is no problem, but the problem is a non really resonant antenna.
After I have redesigned my R7000, the pa works great and the slow tuner also.
I also have a FL 2100B, but as same as in my VHF/UHF equipment (BEKO PA), the transistor pa you switch on and work. You have no problems to allign as you have to do with the FL-2100.
I have the first modell, without RTTY switch, but I will buy again one more.
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| ZS6DX |
Rating:      |
2003-05-06 | |
| Better than expected |
Time Owned: 3 to 6 months. |
After reading the reviews here I nearly did not get a FL-7000, I must say I am VERY happy that I did get one in the end. I believe it is great value for money. It is maybe not as forgiving as a tube amplifier but then no solid state amplifier is. If you use it with reasonable antennas and you do not overdrive it it works 100%. If it trips you have a problem somewhere in your antenna system !, fix it and don't blame the amplifier. I have used the amplifier with more than 10 different radios, FT-990, FT-847, TS-870, IC-746, IC-765, FT-890, IC-706 plus a few older sets, it worked fine with all of them apart from the IC-706MKII, a rig well known for it spike on startup. The IC-706 also had a problem with my T1000 solidstate amplifier. Once the tuner is tuned it is fast, I do not understand some of the complaints I have heard, anyway, if you have a decent antenna you do not really need the tuner.
If I can find a second FL-7000 I will buy it in a second !, it is a great, quiet, cool no hassel amplifier ! |
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| WB6MYL |
Rating:   |
2002-01-13 | |
| got rid of fast |
Time Owned: 0 to 3 months. |
| I had similar experiences to other reviewers. The FL-7000 did not like non-Yaesu rigs and did not like SWR over 1.5; I bought a FL7000 when I bought a new Icom 781 and the amp would go into default with a 1.5 or higher SWR; did not have this problem with the 922, SB-200 or my 30L1; For me, I have stayed with tube amps; more forgiving, easier to tune; experience was several years ago but recent reviews prompted my own review; I had the amp on two of three days before returning to jobber (thanx to HRO Anaheim for taking it back). |
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| W6SZG |
Rating:      |
2002-01-13 | |
| Gets it done |
Time Owned: 3 to 6 months. |
| I got active again after 30 years off the air this summer. Added this to my FT-990 after checking reviews here and at ARRL site. Very glad I did. It loads up well into my G5RV on 40, 20, 12 and 10 meters. Tuner is slow the first time, but then the memory gets you ready to go in 5 seconds or less. As mentioned previously, with a truly resonant antenna output is >600 watts (as on 20 meters for me now) and tuning way faster. It runs cool on SSB and CW, but I did add a tiny extra fan from a junked computer CPU. The convience of having all operations fully intergrated and controlled from the FT-990 transceiver is very, very nice. Getting the pin out data for the band data cable took some doing as the manual was not clear and Yaesu techs did not have the info. The "factory" cable part # is no longer available. A kind "Elmer" on this site used his VOM and gave me the pin-out data to match it up with my FT-990. I will happily share that info with anyone who needs it for the FT-990/FL-7000 combination. Be advised - it is not pin #1 to pin #1 and the 8 pin "DIN plug" on the rear panel is not the standard style/size in pin position or pin numbers. I have multiband yagis and a tower coming this Spring, should be the "perfect" shack after that. Compact and has AC power supply built in. Runs fine on 115VAC. For about $1000.00 used in 10/10 condition, I am very pleased. I like to work DX on CW and SSB, this get it done. |
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| G4IOV |
Rating:     |
2002-01-07 | |
| More than I asked for.. |
Time Owned: more than 12 months. |
I purchased my FL-7000 from Martin Lynch about six years ago, before I came to live in Vietnam. A linear is a must for my QTH where I am 3W2EA.
Don't be surprized to find improved performance as the FL-7000 warms up. The ATU is slow, and the best by far results come from a resonant antenna. With a resonant antenna 800+W is easily achieved.
For my QTH the two internal cooling fans were not enough, and I have placed a fan coil air extract over the top grill. Now it runs warm, but not hot!
The ALC is located at the rear of the FL-7000 and difficult to reach. The unit runs cooler by not connecting the ALC, turning off the ATT. Connect the PTT (reduces static build up), the Band Data cable, and control RF power from the tranceiver.
The FL-7000 is heavy (like most linears) but much more compact than some. Its PSU is internal.
Rated at 500W, it gives far more provided you use a well resonant antenna. 73: Best DX.
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| G4VGO |
Rating:      |
2001-07-19 | |
| Does What It's Supposed To |
Time Owned: 0 to 3 months. |
I have used the FL7000 for a few weeks now and it does exactly what it is supposed to, put out 600 to 700 watts on all bands, including WARC.
On CW, it is fast enought to use QSK with my FT1000D, and on SSB it is clean.
A good match for Yaesu transceivers, using the Band Data cable. It has been used with my FT840, TS570, TS850, and Palcomm 16000A (again QSK).
Not a flame thrower, but a good steady amp, well designed and it also has very good protection circuits that prevent damage before you can do it.
My one criticism, the built in ATU is a bit slow, but you can't have everything for the price!
I'm happy with it.
Bob G4VGO |
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| DK3QN |
Rating:     |
2000-07-24 | |
| reliable performer |
Time Owned: more than 12 months. |
This is my second FL-7000. I bought it brand new at times when the Yen to Deutsche Mark was still ok for us. My current model is already the new version which provides an additional RTTY switch on the front panel. This switch just lowers down the collector voltage of the finals to about 34 volts.
Protective circuits:
The ampifier tends to trip into protection quite easily with high SWR, overdrive or 'spiky' transceivers. I reduced this sensitivity a bit by tweaking the controls. It is now quiet in that respect with clean TRXs.
Built-in antenna tuner:
The built in antenna tuner is terrible. After playing around with it for some time I decided not to deal with it any more. Instead, I bought a second hand ICOM AT-500 which is much faster and reliable.
Fans:
The fans only operate if the temps either of the internal PSU or the RF heatsink call for.
So even after switching it on you will not be destracted by any fan noise. On the other hand, if you run key down maximum power output for some minutes, the fans will come on in two steps where step 2 is like attending a formula 1 racing. But again, this only happens when I use it on key down modes.
Output power/gain:
My FL-7000 puts out a maximum of between 800 watts (80&40m) and 550 watts (10m).
The required drive power is depending on the setting of the rear ATT switch which has the option to introduce a minus 3 db pad. When I use the amp together with my SG-2020 on 80 meters (output about 24 watts) it provides an RF output of about 400 to 500 watts. So the gain of the FL-7000 is quite high, at least on the lower bands.
RF signal quality:
When I had been using my brand new FL-7000 for the first few hours, I realised that the IMD products were rather poor (by listening to my transmitted signal on a second receiver).
The signal quality became much better when the amp had warmed up, typically after some minutes of transmitting.
Root cause: Out of the factory, the resting current of the ampifier was pretty low. Additionally, the bias circuit providing the necessary amout of DC voltage to the 4 final transistor's base was running away as the temperature of the transistors/heatsink was increasing.
So, the resting current started at a low level, causing poor IMD, and then raised up as the unit got warmer, improving IMD.
Solution: you can adjust the resting current for the 2 RF power modules quite easily and individually. I moved the values up to an initial resting current (cold state) per module of about 250 to 300 mA (original value: about 120 mA). After 30 seconds of keying the amp (without drive power supplied !!!) the resting current creeps up to about 400 to 450 mA.
Now you are running your FL-7000 in a condition that will not bother other stations operating some 3 KHz off your channel, provided your transceiver is also clean enough.
Compatibility with TRXs:
Even after tweaking the protective circuit's sensitivity into somewhat 'milder' state, I had problems with some TRX causing the FL-7000 to shut down. I could not use this amp at all together with an IC-706Mk2 and a TS-570. I looked for a root cause regarding the use ot these two transceivers because other TRXs performed flawlessly with the FL-7000, like an FT-990, FT-1000MP, FT-100, various Ten Tecs, IC-746, FT-847, etc.
Looking more in depth into the ARRL test reports (including extended reports) for the two above mentioned TRXs, one can see that both models create a significant RF power spike at the onset of a transmission no matter what power output level you have adjusted. This spike is somewhere at around 80 to 100 % of the maximum output power of the TRX unit thus causing the amplifier to trip into protection because of an overdrive situation.
So, the protection circuit is doing what it is supposed to do: prevent the amp from damage.
Meanwhile I have experienced various occasions where I was happy to have that protection circuit in place. These are the kind of situations where the 'problem' sits in front of the device, like changing the TRX to another frequency without following that procedure at the amplifier as well (e.g. move the TRX to 20 and leave the amp switched to 80 - definitely not recommended for some tube Amp users!). Without protection you would quite likely damage or destroy your final transistors plus the low pass filter, a multi 100 $ event!
Conclusion:
Yes, the FL-7000 has some flaws. The major flaw is the built-in antenna tuner as it is so slow.
On the other hand this amp has proven to be a very reliable performer with a little built-in 'brain' that prevents you from spending alot of money for a service bill.
As this model is no longer manufactured by Yaesu, it's not easy to find alternatives out of current production brands. Either you can find a good-working second hand one or purchase a new ALS-600 (reviews elsewere on this WEB site).
Klaus, DK3QN
(email: DK3QN@gmx.de)
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| KB7UUC |
Rating:  |
2000-07-06 | |
| Only Usable With Yaesu Exciters |
Time Owned: more than 12 months. |
The FL-7000 has had many problems throughout its existence. I purchased one back in 1993 in order to use with my Kenwood TS-690. Although it worked OK on CW (and put out about 600 watts), when I tried to operate it in SSB mode, the high voice modulation level of the Kenwood transciever (characteristic of this brand -- this accounts for their very "hi-fi" sound on the air) caused the protection circuitry on the FL-7000 to blow as soon as I started talking. Yaesu exciters (including the 840 and 990) were much better and the amp would work OK on SSB with these rigs. However, if spoke one word too loud, the protection ciruitry would kick in.
A few years later (1996), Yaesu came out with a mod to the amp which eliminated this inexcusable problem. However, after the mod, the maximum power that I could get out on SSB was about 300 watts.
I sold the FL-7000 in 1997 and replaced it with a good old tube unit (the Kenwood TL-922a). |
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