Generating 100 Watts of output from as little as 5 Watts of input, the Model 418 Amplifier raises the bar for reliable and efficient recreational, emergency, and even contest communications.
TEN-TEC Engineers have utilized state of the art, silicon MOSFET technology to allow continuous 100% duty cycle operation in both CW and SSB modes. The model 418 is also compliant with AM, FM, AFSK, and PSK modes of operation. This amplifier also offers full QSK CW keying plus hot switching protection.
Measuring only 3.625" X 6.5" X 7.6" inches and weighing just 5.4 lbs, the Model 418 will operate from any 13.8VDC (+/- 15%), 20 Amp power source.
Designed to interface with the new TEN-TEC Model 539 QRP Transceiver, the Model 418 amplifier can be easily connected to most low power transmitter designs (1 to 20 Watts). The amplifier's comprehensive User's Manual and TEN-TEC's industry standard Technical Support department make set up quick and easy.
The Model 418 can switch bands automatically or manually. It also has a two position manual antenna switch. Bypass operation allows low power operation until higher power is needed. RF Sensing will automatically switch bands for you when the 418 is keyed with other rigs and the delta button is turned off.
The Model 418's large LCD front panel readout gives the operator essential information about Output Power, SWR, Operating Voltage, and even Operating Temperature.
Posted by Robert W6CRA on 5th Feb 2014
Great little amp. Operation very easy. Looks good too! To get 100 W out, I had to run the drive up to 8 W, but if I run to drive up to 10 w, I get almost 120 W out. This can only be done however, if the SWR is under 1.5
Posted by Maarten on 2nd Sep 2013
The Ten-Tec 418 amplifier is billed as the companion to the Argonaut VI QRP transceiver. I love the Argonaut VI because of its great sounding receiver and a super easy to use front panel. I also enjoy QRP but sometimes it is nice to have more power. So that is where the Ten-Tec 418 comes into play.
First of all this amplifier looks very nice. It has an attractive display and is about the same size as the Argonaut VI except a little taller and heavier. The large display provides plenty of information. The buttons light up in the dark and the display color can be changed to match whatever color one has chosen for the Argonaut VI. It might not be the ideal portable amplifier but sure looks good in the shack. Neither is the Argonaut VI ideally suited for portable use.
The 418 is a perfect match for the Argonaut VI. Band switching is automatic and full 100 watts is easily achieved with 5 watts drive. It can run QSK and the amplifier does not get warm during extended use. It has 2 fans that one can barely hear when they turn on. It has great fault protections and is very solidly built. I makes the Argonaut VI a 100 watt transceiver.
Unfortunately the TX relays are not quiet. They are much noisier than the internal relays in the Argonaut VI. On CW using QSK you do want to wear head phone as the clacking of the internal relays can be annoying. It has a delay button that if used quiets things down. With a little delay the relays do not click with every dit or day but as a consequence one loses the QSK feature. Also the delay times beyond 3 are way too long (>2 sec). I would love to see an even shorter delay time than the one that is provided at the #1 (shortest delay) setting.
It also has an antenna switch for 2 antennas. Unfortunately this switch only functions when the unit is powered on. There is no stand-by provision. So the second antenna can only be used with QRO. Why Ten-Tec did not provided a standby switch is not clear to me.
There is also a separate 6m antenna output. For Argonaut VI users this antenna output is useless as the Argonaut VI does not have 6m. It would have been great if the 6m antenna connector could have been put to use for the Argonaut VI users. For example having the option to configure the 6m antenna connector as a receive antenna for 160 and 80m would greatly enhance this amplifier. The Argo VI has such a great receiver that it is a shame it does not have a separate RX input. Why did Ten-Tec add 160m to this rig if there is no provision for a separate RX input?
There are some ways around these short comings without having to modify the amplifier. I also have a Ten Tec Model 318 amplifier keying interface. Using this accessories it is easy to interrupt the key line towards the 418 with a switch so I can put the amplifier in standby. Also you can built your own little switch box too. Unfortunately when putting the amplifier in standby via this method the Power and SWR indicator do not function in by-pass. But at least one can now use the second antenna connector with QRP. But why did Ten-Tec not think about this? It seems so obvious.
Overall the Ten-Tec 418 is good and most users would not notice the above shortcomings but it could have been great if Ten-Tec would have put the 6m antenna connector to use for the Argonaut VI owners and provided a simple hardware modification for a standby switch.
73 Maarten N1DZ
Posted by VE7IG on 10th Sep 2012
Just wanted to pass back to you that I received the 418 amplifier and it interfaced with the KX3 and my Alpha 8410 perfectly with no hot switching or any other problems, keying both the 418 and the Alpha from the KX3 keying line direct. I really appreciate the ATTN available which lets me use 5 watts output on the KX3 instead of the 1.7 watts without attenuation and sometimes the 418 would give me higher power out on peaks and would overdrive the Alpha on the low power setting. With the ATTN switched in this is not a problem at all. Everything else about the 418 is completely plug and play. A beautiful little amp and I hope you sell a thousand of them!
73 Reg, VE7IG