First Impressions


I have always been one to jump on the latest technology in amateur radio when it has become mature enough to be reliable and when the price has reached a reasonable level, however I have been willing to be an early adopter with the understanding that there may be some unresolved issues that I or the manufacturer would have to resolve in the evolution of the equipment.


My first ham radio transceiver was the Heathkit SB-101 that I built back in the late 60’s.  By the mid 70’s the newer Japanese radios had features that turned my head, such as better solid-state receivers, speech processing, digital read-out and much more.  I liked the idea of digital read-out so much that I purchased a new Yaesu FT-301D.  A great radio, but only the read-out was digital…the VFO was still analog.  There were drift problems, RFI problems, and small annoyances like having to recalibrate the frequency every time you changed from USB to LSB.  When the Collins KWM-380 came out, I was thrilled that there was a radio that was digital through-and-through.  My ‘380 is still a great piece of equipment that can hold up against some of today’s best, although in typical Collins style, it was Spartan in its features and controls, but built like a tank…and nearly as heavy!




Pictures courtesy of the Rig Pix database.



The next big technology advance that got me excited was IF DSP, which was introduced to the amateur community in an affordable transceiver form in the Kenwood TS-870S.  I bought the radio shortly after it went on the market, and was mightily impressed by its ability to create numerous bandwidths down to 50 Hz, its impeccable transmit audio, amazing stability with the TCXO option, and the ability to interface to a PC.  It’s perhaps the best radio Kenwood ever produced, and it is destined to become a legend.  Its biggest problem was that the DSP IF was not bullet-proof enough to handle big signals that fell into the band pass of the radio’s single, rather wide roofing filter.  Serious contesters never warmed up to it.


Knowing how fast technology changes, I knew there would come a time when the big signal problem would be solved, and that along with it would come new features and benefits that would wow me into buying a new rig.  Over a short period of time, we saw the introduction of the original Ten Tec Orion, the ICOM IC-7800 and Yeasu’s FT-9000 series.  All of the new radio’s sported price-tags that were quite a bit above what had been the high end of the playing field, but in the ‘quest for the best’ price is no object, right?  Eh, well we still have to count our pennies and spend wisely, which is why I very carefully considered the options before making the jump to the next level.


The Orion II is truly a radio to get excited about.  The receiver performance published by independent authorities show a virtual dead heat in overall performance compared to “top shelf” receivers that have been tested.  Actually using the O2 under various conditions bears out the testing results. The roofing filters and the DSP filters running in cascade allow for extraordinarily deep-skirted response that cuts away at nearby signals in both CW and SSB.  When using the TS-870 in narrow bandwidths on CW signals, they became “mushy” for lack of a better term, and hard to copy due to high levels of ringing.  I believe the 870’s mushiness may have been a result of group delay or artifacts in the DSP filter that distorted the leading edge of each dit or dah.  The O2, on the other hand, causes virtually no distortion to the leading edge, even down to 100 Hz selectivity, and the ringing is not as noticeable as in other receivers.  The most remarkable thing is when tightening the selectivity, the adjacent signals simply go away, and as the band width decreases below 600 Hz to less than 300 Hz, the band-noise seems to drop down appreciably.  By manipulating the RF gain, and using the Noise Reduction function, a CW signal barely one S-Unit above the ambient band-noise and swamped with nearby strong signals, can be made to sound almost like a code practice oscillator.  In a contest, you can use 300 Hz bandwidth, with the optional 300 Hz roofing filter and simply tune across the band, and signals strong and weak seem to pop up, one-at-a-time, almost like a channel selector on a TV set. The biggest limiting factors are the key-clicks from nearby signals caused by their poor transmit keying circuits and phase noise.  On that subject, the Orion is ‘good citizen’ to other ops with its exceptionally low transmit phase noise as well as its carefully controlled rise-time, which is menu adjustable.


The Orion’s QSK keying is smooth, quiet, fast and easy to operate.  At my station, I was able to easily interface to my second-generation Ten Tec Titan 425 linear, the one with the QSK/PTT switch on the front panel and now, I have no fear that any damage will be done to the expensive vacuum transfer relay, no matter how fast I set the T/R delay.  There are no extraneous pops and no weird AGC pumping when the receiver comes back on between transmissions, something that was not the case in transceivers I have used before.  The keyer seems to run very well, although as of this writing there was still some kind of unresolved electronically-generated click in the side-tone monitor in the background behind the tone.  It sounds almost like the old-time railroad telegraph system that clicked and clacked as the key went up and down.  It’s definitely not any acoustic sound generated by mechanical relays in the rig or the amp.  Ten Tec has been advised of the problem is looking into it.  There have also been reports of some kind of stutter that on rare occasions hits the beginning of a pre-recorded CW memory send.  The thought is that it happens when there is too much going for the CPU to handle all at once if adjustments are being made just before or during a memory send, or perhaps contact bounce when the Send 1, 2 or 3 button is pressed.  At any rate, I have only seen it a couple of times in nearly three weeks of daily operation, although admittedly, I don’t do much CW work.


Early on, I noticed that the Orion has true Band Data output available on the back panel for both the Antenna 1 and Antenna 2 selections.  This is a quantum leap over other radios I have used such as ICOMs that use a varying voltage requiring a level converter to use the output for automatic antenna selection, or Kenwoods that have only the RS-232 requiring interpretation of a digital data stream.  The Orion uses a ‘no-brainer’ system where each of 10 pins, corresponding to the 10 HF bands, goes logic low as each band is selected.  I use an Ameritron RCS 8-V 5-position remote antenna selector at the top of my tower for all my antennas, and it took me no time to realize that my antennas could automatically follow the radio as I switched bands using this great feature.  While the relays in the Ameritron could have been connected directly to the Orion II (13.8 VDC is provided on the same connector, and the logic transistors can pull 250 ma) I was afraid to have any wiring running parallel to a “lightning magnet” like a tower going right to my shiny new radio!  Now, I realize that the antenna connector itself is in that class, but my transmission lines run through lightning arrestors before entering the shack and the O2 has a good-size RF choke and an internal spark-gap tube on each of the antenna inputs.  The solution was to use relays to isolate the radio from the remotely controlled relays at the top of the tower.  The relays and some LED’s were wired into an external box, with an additional relay rigged to turn off rig control when the Ameritron control box is turned on, allowing for manual antenna selection just by flipping on the Ameritron power.  Although I made some initial wiring screw-ups, they are now fixed and wonder how I ever was able to live without this valuable feature!


The Orion II shines when it comes to SSB, in rag-chew, DX pile-ups and contests, although I have not had a chance to use it in the contest mode yet.  The ability to easily control the bandwidth and PBT allows for precise tuning that zeros in the desired signal.  The advantage of that became obvious while chasing the 3Y0X DXpedition which neatly coincided with my Orion II’s arrival.  My big challenge was to get them on 75 meters, which was not an easy task.  Signals were often just above or just below the local noise level, and there were monster signals 5-15 kHz up where they were listening.  My ‘weapon of choice’ was having the second receiver so I could track exactly where they were listening.  Now, many transceiver have two receivers, and almost any radio can swap VFO’s to listen on the QSX, but the ability to direct the sub-receiver into only one side of the headphones, with the 3Y0 directed to both, made it easy to make sense of the incredible racket.  This was even more effective in working them on CW on the other bands.  The ability to shape the AGC constants also proved to be very helpful, as was the Automatic Notch (AN) to kill the tune-up carriers that seem to pop up at the worst possible time.


A note on the AN and the manual notch functions:  in the current firmware version (2.030) the AN and notch operate instantly to remove the tone from the audio, however, it does not reduce the level of the signal on the S-meter, hence an S-9 carrier over an S-3 signal is knocked out to the point of being inaudible, but the S-meter still stays at S-9 and the AGC is consistent with S-9, making it hard to hear the desired signal.  I understand that this is not the way the original Orion firmware in v. operated, and it was not the way my old TS-870 worked.  I much prefer the old way where the carrier goes away, and the AGC level and S-meter both return to the level of the desired signal.  Many others on the Ten Tec reflector have made the same observation and have commented that it now seems like “an audio-only notch” instead of the traditional IF notch.  Actually, there is no difference since everything, including the DSP passband functions, NR and NB functions, are done in the 14 kHz IF, which can be thought of as a glorified computer sound-card with a 14 kHz bandwidth, even to the point of having two channels, one for the Main RX, the other for the Sub RX.  Just like any good computer sound-card, it can be made to behave in any way and do pretty much anything the DSP programmer can imagine and implement.  Such is the wonder of the new world of Software Defined Radios!


Since the bulk of my operating is SSB rag-chew, and with my background as both a commercial broadcast Air Personality (that’s ‘disc jockey’ for those of you in Rio Linda…) and engineer, I can say without reservation that no radio would land in my shack if I was not convinced the that transmit audio was nothing short excellent.  With only a few very minor complaints, I can truthfully say that Ten Tec has delivered on that requirement in the Orion II. The audio response is smooth, and can be adjusted to any bandwidth up to 3900 Hz.  There is no audible distortion, even when driving the mic input with higher than normal levels.  I precede the Orion II input with the W2IHY 8-Band EQ and the EQplus processors, although even with them both switched out, the audio is clean as can be and gets lots of good comments.  With the IHY boxes on line, the audio is spectacular.  Note that I get this good sound even using a cheap mic—a ‘$22 special’ Audio Technica mic, typically used for PA systems that I got from Broadcast Supply Worldwide in Seattle.  The important thing is that it is a low Z balanced cardioid dynamic mic with an XLR connector.  After several months, I finally got around to purchasing a Heil PR40 and was amazed at the improvement!  I found that there was not nearly the amount of EQ needed to get the sound I wanted.  In fact, running the PR40 directly into the radio with no other produced a full-range, broadcast-type sound.  If I could only afford one addition to the Orion II, it would be the PR40.  Tests with the Heil HC5 in my Pro Set headphones also produced great results, especially for contest/DX work where intelligibility is important.  This can be aided by the Orion II’s quickly-adjustable transmit EQ to give a crisp clear “ear piercing” sound so essential for busting a pile-up.


.The Orion II’s VOX is hands-down the best I have ever encountered in a transceiver.  It is so fast that there is no noticeable loss in the first syllable when it turns on. It holds steady until you quit talking and promptly, without clicking, popping or pumping, turns back to receive.  I often operate with an informal net on 75 meters of folks who get together each night and operate using ‘fast break-in’ VOX or PTT.  The O2 VOX works so fast and smooth that I can interject one-syllable reactions in between words, mid sentence while someone else is speaking.  Almost like a face-to-face conversation.


Part of the success of the Orion’s good audio is found in the mic preamp IC, the Analog Devices SSM2216 chip, which features a built-in AGC/limiter function, low noise with the ability to handle very high input levels while maintaining low distortion, to pre-condition the audio before proceeding to the A/D converter.  This is the same IC that is used in the compressor section of the highly-praised W2IHY EQplus box.  The chip costs $2.75 in quantities, and while this may not seem like much, remember that equipment designers are under the gun to shave pennies wherever possible.  I suspect that a plain-Jane op-amp IC could have been used, probably at a cost of less than $.15, and while the two other $10K+ rigs on the market may have SSM2216’s or something even better, you probably won’t find anything like this in less expensive radios.  This is a home-run for Ten Tec!


Folks who are into AM will find a lot to be happy about now that Ten Tec has fixed the problem that prevented AM from operating in an earlier version of the O2 firmware.  A frequency response test shows that the audio is +- 2dB from 20 Hz to 3800 Hz. You can see the actual test results here, but in a quick summation, the low frequencies are accentuated over the mids and highs (1.8 kHz and up) by about 4 dB, but the high end extends to 4 kHz with a gentle roll-off to -12 dB (relative to 1 kHz) all the way up to 5 kHz.  With a mild boost of 4-6 dB in the high end, this starts to sound like a broadcast transmitter!  Even the distortion appeared to be low, less than 1% based on harmonics visible on the spectrum analyzer.  I checked into the AMI net recently and net control told me I sounded as good as any of the guys with boat-anchor, plate modulated AM broadcast transmitters that check into the net.


Some items I thought about before buying the Orion II:  

  1. Would it have noise/hiss/hum from the headphones or speaker outputs that was internally generated (I had problems with other radios in the past).  Answer: No, none, zip, nada.  When you turn down the RF gain all the way, the audio is absolutely silent.  
  2. Would the tuning knob have a good, smooth feel and the tuning rate be comfortable?  Answer: Yes…no doubt. Fast selection of tuning rates, and menu selected options can make the tuning rate anything you want, and the radio “responds to the helm” positively and quickly, no matter how fast you spin the knob.  There is no ‘catching up’ ‘jumping’ or other anomalies.  I haven’t tried to adjust the drag on the tuning knobs since they felt fine to me right out of the box, however there is a way to change the amount of drag if you want it tighter or looser.


Since purchasing the rig, I have tried it with a number of partial and full-featured computer control and logging programs including AC Log, Ham Radio Deluxe, N4PY, LOGic 8, and several others. No problems have been encountered in any program that supports the Orion or Orion II.  Audio I/O’s and external keying from my laptop were easy as can be.  My laptop does not have a serial port, but a cheap, 'no-name' USB-to-serial converter worked fine right out of the box.


Now, on to those minor grievances I mentioned earlier.


1)        The transmit frequency response is quoted in the specs as having a 6 dB roll-off at 50 Hz with the transmit EQ flat and the LF response set to 50 Hz.  In fact, I measured it at -15 dB, with a ‘knee’ that starts about 300 Hz.  While this may actually make many mics in many shacks sound better, and contributes to an over-all cleaner sound, those of us who strive for the “full” audio sound notice the missing bass.  Running the EQ up 6 dB causes the lower frequency response to get better, but at the expense of increasing the 300-400 Hz levels to +3 dB.  The high frequency response looks fine and with flat EQ, the rest of the spectrum is essentially flat.


2)       There is a slight problem with RF getting into the rig, especially on 10 meters, and others have reported similar problems.  I only noticed it at my shack when the beam was pointed directly overhead, positioned about 45’ feet away, and even more so when the amp was on, running 1.5 kW.  It may be surprising to know that the RF is not entering the radio via the mic input, which is usually the first suspect with troubleshooting such problems.  I found that the main point of entry was the headphone connection, and a smaller problem was associated with the CW paddle connection on the back panel.  It took a good-sized ferrite torroid (Amidon FT-240-43) to fix the headphone problem, and a small “clamp-on” bead for the paddles wire.  That done, there is absolutely no hint of RF at any power level, band and/or antenna position.  Of course, good grounding is always important, and my newly-rewired shack was designed and built with that in mind.


3)      The Orion II features an “RF speech processor”.  Of course it’s not really RF (unless you consider 14 kHz as RF)  as the literature eventually reveals, but rather a DSP function in the logic section.  From what I can tell, it works more like a very fast AGC than a traditional clipper.  The good news is that it adds no distortion.  The bad news is that it adds no distortion.  Not that distortion in and of itself is good, but by clipping the audio, most processors are able to increase the average RF level to the point that sluggish analog watt meters start to show higher average output levels, which should be consistent with “blowing a hole in the band” in pile-ups and contests.  By not severely clipping the audio, excellent fidelity can be maintained at the lower settings, which is an advantage as well.  My first weekend of using the radio, I jumped into a pile-up at 14.205, speech processor set at 3, low end bass raked out with the EQplus.  After the second or third call the DX came back to me and made the unsolicited comment that my audio “just seemed to pop out from all the others” even though signal strengths were all about the same.  That sent chills up my spine, and may indicate that “less is more” works in SSB audio processing, but I still like seeing my old Collins 302C-3 watt meter “reaching for the sky” when I slowly shout my phonetics (‘Noooorwaaay ssiiiiixxx….’etc.).  The jury is still out on this but it would be nice if a clipping effect could be programmed into the DSP to emulate the sound of the old DX Engineering, Vomax and Datong processors in the higher settings of the SP, maybe in the 6 to 9 range.


4)      Something is wrong with the AM detector in the receiver.  It sounds distorted, even when listening to broadcast stations on the AM band on the Sub RX.  Even the slightest selective fading makes the distortion even worse, especially on speech.  Adjusting the AGC, RF gain, adding attenuation, reducing the ‘taps’ on the bandwidth skirt and selecting the 20 kHz roofing filter did not cure the problem.  This could be as simple as overdrive of the digital IF by the preceding stage, or perhaps there is a tweak needed in the DSP.  Whatever the cause, I hope Ten Tec fixes the problem.  I have found a way to mitigate the problem and make AM in general sound better when using headphones.  Here are the settings to try:


1)               In the Audio Menu, route the Main receiver to the Left and Sub to the Right

2)               Set both Main and Sub Receivers to AM

3)               Set BW on both to 6000

4)               Set PBT on the Main to -2500 and the Sub to +2500

5)               Make sure the ATTN, AGC, Step, and RF Gain are set the same on both receivers

6)               Set the Main and Sub receivers on the same VFO


This independent sideband detection arrangement sounds spectacular and reduces the normal distortion caused by selective fading as well as the DSP distortion in the radio, while making the recovered audio bandwidth wider.  Yes, it does add “platforming effect”, that is caused by the selective fading, which makes the “center” of the audio channel seem to shift left and right.  Despite that, it makes the great equipment that many AM’ers are running on the bands sound amazing!  When set like this, AM sounds better to me than it ever has before.


Another thing to note is that the ‘digital voice keyer’ memories apparently run through the SP when recording and not when playing back.  There is nothing wrong with that, but it may be different than other rigs where the speech processing can be changed on a ‘canned’ message.  The other complaint that is often heard is that the Send 1 and Send 2 memories are good for 4.54 seconds (only on voice—CW space is quite large), just enough to give your phonetics…if your call is relatively short.  Good luck if you are KL7/WB7XYZ!  If you need more time, the Send 3 memory can be used for up to 28.1 seconds, but the memory is lost when the Orion is turned off.


There have been reports about the warm-up frequency stability of the Orion.  Being the type who likes to know exactly “what is the frequency, Kenneth” (remember the 1986 Dan Rather knife-point incident?), I was a bit concerned about this.  When my O2 arrived, I placed a temperature probe in the A10 board compartment near the 44.5 MHz Siward TXO32 master TCXO and tracked the heat and drift from start-up.  I noted that it does get quite warm inside, reaching about 115 degrees F in a 70 degree F shack.  The frequency drift seemed to track the temperature rise over much of the time until full stabilization was reached, which took over two hours.  This is consistent with the results in Martin, AA6E’s original blog


It occurred to me that drift could be mitigated simply by adding a small CPU-type fan in the enclosure, set to blow cool air on the TCXO.  I started with a 40 mm 12 VDC brushless fan hooked to the bulkhead with wire-ties positioned over the TCXO module.  The results were striking.  The maximum 20 Hz drift on 15 MHz WWV was reduced to 8 Hz.  The only problem was that the acoustic noise was louder than I was willing to tolerate for the long term.  The second attempt used a 50 mm fan, carefully attached with thick ‘double sticky tape’ applied between the edge of the fan and the bulkhead, and an addition piece of standard foam weather-strip (one-side sticky) backed up with more double sticky tape on the stationary flat side of the motor, attached to one of the larger modules near the TCXO.  Much better!  The noise was nearly eliminated, and the increased airflow brought the unit to stabilization in a much shorter time.  With the fan mod, after a 15-minute warm up period, the radio is no more than 3 Hz off 15 MHz WWV, and after 30 minutes it is always with in +- .5 Hz, an astounding .03 ppm after stabilization.  Of course, if the shack changes temperature, the unit is likely to drift a bit, and there will be long-term crystal drift requiring that the alignment procedure be performed every six months or so, especially in the first couple of years.  Power for the fan is obtained by snaking a wire out the back panel through the #2 Band Data connector opening and using the 13.8 V RCA connection on the back panel which is protected by a 2-amp, self-resetting, thermal circuit breaker.


Another thing of note is that the Main RX and Sub RX are usually 6 Hz out of sync on all bands when both are dialed to the exact same frequency.  There has been some debate about this and it is believed that this is a function of the DSP.  If that is the case, it may be possible for the Ten Tec engineers to add a menu item that will allow for a minor trim to put the two receivers in sync, which is helpful for diversity reception which is touted as one of the radio’s many features.


The last area that should be addressed by the TT engineering department is S-meter discrepancy.  The RST system in general has been a hotly debated topic since it was introduced around 1934, and for a good summation of the history and current thinking, I strongly recommend reading L.B. Cebik’s excellent article on the subject.  Running a test with an HP 8640B signal generator and a Tektronix 2712 spectrum analyzer I found significant variations from the generally accepted “norm” of S-meter calibration, which sets the S-9 level at 50 uV, decrementing 6 dB per S-Unit.  You can look over the results of the test here.  The short version is that with the preamp off, the radio is stingy by 2-3 S-Units below S-9, and overgenerous by up to 22 dB when over S-9.  Adding the preamp pushed the ‘generosity’ up to a whopping 35 dB.  I suspect this is simply a problem that can be corrected in the firmware.  Beside getting the basic linearity better, it would be nice if there was a menu selectable option that would reduce the reading by 12 dB automatically when the preamp is switched in, the same way the TS-870 does.  A user on the Ten Tec reflector pointed out that when the Sub receiver is switched to the same antenna as the Main, the S-meter drops by 6 dB, which I confirmed.  This too could be corrected automatically by the firmware when it detects that the two receivers are sharing the same antenna.


It seems like I have a lot of complaints listed, but rest assured that I have exhausted my complaint list, while barely scratching the surface of the list of things I like about the Orion II.  I’m sure that most of these minor problems will be fixed in time.  I never expected to have a perfect radio delivered anymore than anyone expects Microsoft to deliver perfect software in the first or second release or “SP”.  For a non-software based radio this would be a problem, but with the easy updatability of the O2 and its modern SDR and DSP technology, it becomes part of the challenge and the fun of helping a responsive American manufacturer build the perfect radio.