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Reviews For: NEC CQ-301

Category: Amplifiers: RF Power - HF & HF+6M

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Review Summary For : NEC CQ-301
Reviews: 3MSRP:
Description:
SSB Linear Amplifier, 1.9-28 MHz, 2x 3-500Z
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0034.7
ZS1ZC Rating: 2021-03-22
Heavy Lifter for QRO Time Owned: more than 12 months.
After I built an HF linear around a single 3-500Z, I was in the mood for a pair of them, and looked around for a Kenwood TL-922 to complement my TS-830S series. The ZS market is fairly limited, so none was available at the time, but I was offered an NEC CQ-301 that needed a bit of care. After replacing the tubes with RF Parts 3-500Z’s (it had arrived with 4-400’s in it), replacing the grid circuitry that someone had inexplicably ripped out, and putting a couple of little brass shoes on the abused bandswitch, I had a full legal limit amp for all traditional HF bands (no WARC positions on the bandswitch, but as ZS6DJD points out, it will still load them up on adjacent positions).

Except for a few protection circuits (e.g. soft start), the CQ-301 has an almost identical circuit to the Kenwood unit. Built like the proverbial tank, this amp delivers a kilowatt PEP with not much more than a blush. It’s easy to tune and the matched input works a treat with both tube and semiconductor final rigs (e.g. TS-830S, Drake TR-7).

The 301 is fundamentally the same as any other grounded-grid dual-3500Z amp and performs accordingly. So it’s in the same league as a Henry 2KD-5, Heathkit SB-220 (though better production quality), or the Drake L-7. The build quality is really very good and there’s plenty of supply power for well over a kilowatt key-down and 1.5kW SSB PEP into a load.

Although it’s a desktop unit, this amp is heavy – as you’d expect it to be. It has really solid controls and multifunction meters. The HT supply voltage is switchable to suit transmission mode. It has a heavy-duty antenna relay (as you’ll tell from the relay sound), and a sizeable fan for cooling the tubes that is quieter than I expected.

Although it doesn’t have the elegant lines of the Kenwood TL-922, it is nevertheless an attractive piece of kit that sits extremely well in a shack. If, like me, you were after a Kenwood, or maybe a Drake, and one of these comes around – take it.
ZS6DJD Rating: 2017-09-13
good linear 800w to 1300w out depending on valve condition Time Owned: 6 to 12 months.
Hi guys I this bought this linear to get something that would give me 1kw out as we have just recently been allowed to use 1kw in South Africa. After the finacial crash wich hit the whole world in 2008 prices went crazy in South Africa. A good new 1kw linear can cost as much as 60 thousand or more in South Africa money. So I bought this old linear from a fellow amateur for 15 thousand he also had a 2kw alphin linear for 75 thousand to much for me.

So now I have had this linear and used it for about 10 months. It is big and heavy difficult to carry around. Not for mobile use for sure, but apart from that it is a very good linear gives you 800w up to 1300w out depending on the condition of the valves with 100w of drive. Uses 2 3-500 tubes My valves in this linear have seen a bit of use so I am getting 800w out on all bands 20 to 10 including warc bands. So those who say it cannot do warc bands are dead wrong.

With this linear on 20m I have been 59 59+ from South Africa into Europe on most nights 2017 using only a TGM 2 element mini beam 18m of the ground. So present poor band conditions don't seem to be a factor for me. I believe the keenwood TL 922 linear maybe a copy of this linear but a bit smaller. But I think it works a bit better than 922 and is a better linear than the 922, but I have never used a 922. It is built like a tank with very high quility workmanship.

The best part about this linear is that you can drive it with more than 100 watts so if something goes wrong your radio won't damage this linear. All that will happen is that is will give you more power out. Who knows you might get more than 1300w out. I believe one can drive this linear with up 300w with out any damage. Also It comes out in a brown colour makes a nice change from black or silver.

So all round a good linear. If you find one in good condition and you want a brown thing instead of silver or black with 800w to 1300w out and the price is right don't hesitate buy it.
PA0FRI Rating: 2003-07-15
Good workmanship Time Owned: more than 12 months.
Nice build with 100% transmitting components, good workmanship. Quiet fan, noisy T/R relay. Key-down output 1250W at HV 2250V/750mA. On 10m otput about 1kW. The tuned input circuit has to be retuned for the present transceivers. No WARC bands.