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Reviews Categories | Transceivers: HF Amateur HF+6M+VHF+UHF models - not QRP <5W | Ten-Tec Century 21 Help

Reviews Summary for Ten-Tec Century 21
Ten-Tec Century 21 Reviews: 35 Average rating: 4.6/5 MSRP: $299
Description: Morse only medium power rig of the 1970's.
Product is in production.
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N4EEB Rating: 5/5 Sep 27, 2016 18:33 Send this review to a friend
Fond Memories  Time owned: more than 12 months
This was my first "brand new rig", as a young teen after upgrading from a Heath DX40 and SX-100 receiver. Oh, the years of fun I had with this rig as a novice. I was very active in traffic handling with it and even played around in the Novice Roundup, 10-Meter contest and Sweepstakes. And, of course, many, many cw ragchews late at night with the old timers on 40 and 80 meters. I literally worked this little rig until the VFO knob would no longer operate. I could have repaired it I guess, but I sold it. What a fantiastic little rig.
AA4OO Rating: 5/5 Dec 13, 2015 12:20 Send this review to a friend
Fun doesn't get simpler than this  Time owned: 0 to 3 months
My review with photos available at:

Since getting back into HAM radio with my focus now on CW and QRP I have some strange fondness for TEN-TEC equipment. Ten-Tec has made some quirky radios with legendary full break-in QSK and supposedly smooth, quiet receivers for CW operators for a few decades now. So when a Craigslist posting leaped into my browser window (I don't know how that happened) advertising a seemingly pristine late-70s rig that had supposedly been reworked to a perfection, all for $140, I just couldn't pass it up... well at least the price in the ad was accurate.

The Ten-Tec Century 21 is an interesting transceiver. In the simplest sense it was an ideal radio for the Novice Licensed HAM operator of the 1970s. It is a CW only transmitter. It doesn't require fiddling with a resonant tank circuit of the typical tube radios of the era to work out resonance. It has a built-in power supply that runs off 115-120v mains. It doesn't use a superheterodyne receiver but a direct conversion receiver (Ten-Tec called it a double direct conversion receiver). This resulted in a simplified design and good selectivity but without the IF there is no AGC so be ready to work those RF/AF gain knobs. It also has easy band changing and reasonable filtering. From web searches and reviews its most common problem is a PTO that has to be rebuilt every few years. The Ham I purchased mine from said it had been rebuilt. It doesn't slip (yet) but it's kinda stiff so I expect a PTO rebuild to be in my future. I spoke with a ham I work with who has rebuilt one and he said it's not difficult, simply time consuming (but he repairs electronics all day so YMMV).

I have used this radio for a couple hundred contacts at this point and all I can say is it is a blast. It has beautiful audio but a horrible sidetone.

As long as the band isn't crowded it is incredibly fun to use. If the band is crowded then you're dealing with in essence a 2.4kHz wide audio spectrum with an audio filter in front. The cutoff isn't very steep so you'll be listening to a few stations at once. I'm learning to listen through it and it's a good skill to learn to ignore off frequency stations.

The radio is just beautiful to look upon. It has such lovely simplicity that you'll want to use it.

Tune a station and fiddle with the offset. When you encounter QRM from a nearby station simply twist the offset to the other side and hopefully you'll find some relief. It's about the only control apart from the RF gain you touch during operation.

Recently I've been operating it by turning AF to max and using RF gain to control my listening volume. There is no AGC and I was previously riding the AF but it's easier to control the RF gain.

Maximum output is around 30w on 80m & 40m, 20w on 20m, 10w on 15m and a bit more on 10m. But with a radio this old I don't want to push it and generally make most contacts at QRP levels.

Here is a video demonstrating the filtering:

And another video of the radio in operation:

If you love CW you'll want one of these. Get one.
N0TES Rating: 5/5 Jan 29, 2014 20:23 Send this review to a friend
Used for hundreds of hours  Time owned: more than 12 months
Ok, so my life growing up was only about amateur radio and sending CW. Nothing else really mattered to me. For years I pounded a brass key on my Century 21. Full break in, yes. Fun? Yes? It was reliable till the day it was hit by lightening. Fortunately that was about the time I started college, which was probably a blessing, or I'd have just continued on sending CW rather than graduate, date, and start a business that builds amateur radio antennas. Oops, back to amateur radio! Guess I've come full circle! - Steve, Alpha Antenna
N3HEE Rating: 5/5 Jul 23, 2013 05:22 Send this review to a friend
Outstanding Fun Radio!  Time owned: 0 to 3 months
I recently found a super clean Century 21 at a local hamfest for cheap. Took it home and fired it up and it worked just fine with only a few minor issues. The dial was way off in frequency, the offset knob was upside down and the drive button had been disconnected. After calibrating the dial and correcting the offset knob the rig is a real joy to operate. The PTO operates very smooth. This radio was way ahead of its time. This is my first Ten Tec radio and wont be my last.
KC2SIZ Rating: 5/5 Jul 13, 2013 07:45 Send this review to a friend
CW operator's dream  Time owned: more than 12 months
I wonder if there is ANY modern, commercially-built rig with QSK as beautifully smooth and silent as this rig's. I seriously doubt it. If you like CW, do yourself a favor and pick a Century 21. You will not be disappointed.
KA0HVE Rating: 5/5 Jul 2, 2013 13:25 Send this review to a friend
Solid, no frills CW rig.  Time owned: 6 to 12 months
In 1980 when I was studying for my ham license I was going to buy either the C21 or a Kenwood TS520SE. I got the Kenwood (and still have it) but kept wondering about the C21.

Well, I got a C21 late last year, life got in the way, then Field Day a week and a half ago got me motivated and I set up the C21.

I've been wanting to work CW at QRP power levels for years so I cranked down the drive so that my power meter shows under 5 watts. The little rig just amazes me. Simple to tune, good filters, good receiver, clean tone, etc. I wish I had bought one of these in 1980.
KB3RMX Rating: 5/5 Jan 27, 2013 17:46 Send this review to a friend
About The Best  Time owned: 3 to 6 months
Of all the high end and low end transceivers I have owned(I've had just about all of them),I have to say the Century 21 is about the best I've owned. Bought mine off of Ebay a few months ago. Found it very simple to use, not quite qrp, but puts out enough for cw use. The only drawback I had on mine was the cheesy push buttons for the zero-beat and drive, they kept getting stuck in the in position. I replaced them both with newer push button type switches and they work great. I have the digital model (574). The readout is not 100% some of the pixels in one slot does not light up, but thats very minor for me. Was wondering if that can be fixed. Needless to say I am very happy with the rig and have made quite a few contacts with this rig. Its built very well. I like the modular construction of the circuits
I've always been an Icom user, but I'm thinking about going TEN TEC for a base rig. I'm going U.S. made this time. Great work TEN TEC.
NZ0T Rating: 5/5 Sep 4, 2012 16:29 Send this review to a friend
Fun ole rig!  Time owned: 0 to 3 months
I have always been interested in the C21 and found one a few days ago at a hamfest for a song. I've been having a ball with it. Once I figured out the nuances of the direct conversion receiver I have found the C21 is easy to use and performs very well for such a simple design. The 20-30 watts it puts out are plenty for CW work and the filtering works well. It's not perfect nor did I expect it to be. The DC receiver makes the bands seem crowded and I really wish it had WARC bands but I highly recommend the Century 21 for simple CW fun.
KA0AAM Rating: 4/5 May 1, 2012 12:28 Send this review to a friend
Excellent Radio  Time owned: more than 12 months
Why it didn't get a 5. . . .

The finals. . .the finals on this rig are very poor. About once time a year, I would have to replace the finals. . .even when running a flat SWR. I tried lowering my output to 50 watts, but to no avail.

Now, with that said. This radio is the absolute BEST CW rig on the market. You can't have a better cw rig IMO. I worked many countries, states, and counties. It is easy to operate, you can tune BOTH sides of the CW signal, and the CW filter is fantastic. It was my main rig for many many years.
K1YRW Rating: 5/5 Jan 8, 2011 11:35 Send this review to a friend
Old Reliable  Time owned: more than 12 months
I bought my Century/21 new back in '80 and for a few years it was my main rig. Worked pretty near 100 countries using the rain gutter for an antenna. After a few years ran it mobile in my Jeep with a ham stick antenna. Eventually the rig quit and it sat on my basement floor for about 10 years until last summer when I decided to bring her back to life. All she needed was a 40m and the 80/20m xtals and an alignment. The whole repair including a good cleaning took about half an hour. Got the xtals from Ten Tec. Seems like they still support this rig. Surpriseingly enough the PTO was just fine. Now she looks and works like new and once again is sitting proudly in my main shack ready for the next 30 years of QSO's.
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