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On the Yaesu FT-1000MP Mark-V for example, the shape of Collins filters passband is very effective at removing noises on sideband, without impacting the desired signal. The profile of these Collins filters is similar to a square wave, showing very short skirts, what allow to this system to eliminate very easily a QRM located a fraction of hertz near your frequency. Better, thanks to its DSP functions (Enhanced DSP like IDBT and contour and several others) the Mark-V is able to extract the weakest signals from the background hash where most of its competitors fail. With its armada of filters the Mark-V cannot lost any signal in the QRM. Very few other models can pretend to reach such a score, even not the Kenwood TS-2000 or the Icom IC-756PROII transceivers, maybe its successor the IC-756PROIII that shows an improved third order Intercept Point and globally better performance. But today only the Ten-Tec ORION is on par with the Mark-V if not in all, in many conditions of traffic.
On the other side, using integrated circuits, if the digital filters enveloppe is badly programmed it can sometimes looks more like a gaussian curve than to a square wave, with such specs that the weak signals are not completely filtered at both extremes of the filter passband; they will capture the AGC and will still be heard. In these conditions you can never reach performances of a Collins mechanical filter. For decades Collins filters, internal of external, have proven their quality. Of course such filters are expensive, from 150 to more than 250 € per filter, and you need as much filters as you have bands to work. An all set of such filters can cost more than 600 €. Now see the DSP noise reduction filters for
example, that we found in most RTX. They are powerful features that no ham
could no more bypass. In usual conditions the adjustable noise blanker of
the Ten-Tec ORION or the one of the FT-1000MP Mark-V is one of the best
that you could hear. The greatest N.R. is perfect for all but very noisy
conditions. Cranking the noise blanker all the way helps you eliminating
even the most stubborn pulse noise like power lines or engine noises that
other NBs (like the TS-570) won't touch, without compromising audio
quality. SSB audio is very customizable for either fidelity, or cutting
through a pile up using compression.
Power side, the IC-775DSP and the FT-1000MP transmitters develop 200 W PEP out and do not even get warm during long SSB QSO or at 100 W using PSK31. This supplemental power may add a 3 dB to the TX signal, improving a bit a CW signal lost in QRM, or can be useful in driving an amplifier. At last, as many digital high-end rigs the IC-775DSP has a sub receiver, although not as flexible as the Yaesu FT-1000MP Mark-V, that allows you to listen at 2 frequencies at the same time. Like Yaesu, Ten-Tec has also choosen the double receiver. Why using a double VFO ? Imagine that there are two pile-ups working on the 20m band. If the first station is hard to work you can switch to second one and try to work the second DX, keeping an ear on the lower station waiting a lull in the traffic. A double VFO is also very appreciated in CW (or even SSB) when working a DX whose QSX frequency shifts regularly of a few kHz. So such a feature is great for spots and split operations. The TS-570D has well an A/B VFO push-button that can be very useful in split operations when the operator uses a fixed QSX (e.g. "up 5"), but it makes DX spotting moving in frequency (e.g. "5 to 10 up") or working in CW difficult at best ! Now, personnaly I think that it should have been more interesting to use the space occupied by the Sub VFO to add more DSP controls or a spectrum analyzer, an option included in all new Icom. Your antenna system
When these criteria are not taken in account, the reason of missing such DX can simply be a question of propagation or of a (relatively) too low power to reach that station. Therefore, before the amplifier, I suppose than you want to buy a directive antenna, not only for ragchewing in local QSOs where it is useless, but mainly for chasing DX stations, I mean stations located on other continents, at 8000 km away and more. It should be directional with a substantial gain in order to well listen and be also heard by your DX station. Even on shortwaves this is sometimes a challenge that requests a performing antenna system. In addition your transceiver must be properly coupled to the feed line and itself correctly coupled to the antenna. Some QSLs recently received
When using a Yagi or a quad you will quickly discover that you have no more use, or almost, of a linear amplifier because the QRM of near stations has been reduced of 20 dB or more in all directions excepting in a narrow beam toward your DX station; now you are able to work the world with 100W or 200W PEP even during minima of the solar cycle or when propagation conditions are poor for low power or omnidirectional stations. In fact using a beam offering a high gain (say over 5 dBd with a F/B gain over 20 dB) I should say that you have practically a private conversation with your DX contact. This is of course a caricature but used together with a DSP transceiver, your beam can do miracles, or almost. Working with a high-end transceiver and a big gun is thus very exciting as you really don't lose your time in calling DX in vain due to your small installation. Of course such equipements have a price and not everybody can invest a "fortune" in his or her installation. This is a question to debate between you and your conscience. The purchase, operating manual That you like ragchew in local QSOs, work DX stations or contests, you will recognize that depending of your activities on bands, the two main categories of transceiver, the mid- and high-ends (there are probably no more low-ends or "bad" transceivers on the market, excepting maybe some home-maded) give not similar results in the field. There is on the one hand what says the marketing, and on the other hand what are using hams. Do never believe at 100% advertising or salesmen. The best dealer could sale you the worst RTX ever made as being the nec plus ultra model if you buy it like a cat in a bag. A transceiver being an expensive piece of hardware (with prices ranging usually between $1000-$4000, as much in euros) and often a durable investment (at least 10 years), you have interest to select it with care if you do not want to regret your purchase some weeks later. To prevent any mistake you have no other choice that testing it to a friend or to ask to rent a model to your dealer to test it in your working conditions. This latter recommendation is however the most difficult to meet as few dealers accept to rent RTX or any aerial knowing that most users abuse of this opportunity to use them in contests with the additional risk to no more be able to sale the product once used or damaged. Hopefully, for contests manufacturers can sometimes help you.
If you can't get a transceiver for rent or can't visit a close friend using this rig, try to read as many reviews as you can, read the technical threads on forums to forge your own opinion. Read also lab tests and reviews from ARRL (by subscribing to their organization or via a radio club) in understanding well their results, what need some habit. Have the critical spirit and balance all opinions to weight the pro and con of all comments. At last if you really need the best transceiver, equipped with the finest DSP, direct access keys and ergonomic menuing, do not listen (too much) to the OM who just bought a new rig. First he lacks of practical experience and cannot yet compare performances of his new RTX with his previous one. Then in case of problem, it is always delicate to confess to be mistaken when you are a technician (and successfully passed the examination). Check also the QSLs you received from DX-peditions or contest teams to know what is their equipment. Like you they have looked for not only an excellent transmitter but the receive module had to be the nec plus ultra in terms of performances and overall ergonomy. After this analysis you will be much better prepared and in a well better position to judge the quality of the transceiver that you covet. Make the good choice To conclude, can we say that the Yaesu FT-1000MP Mark-V (or the few high-end transceivers list above for that matter) is worth its price ? Well it depends. Over three times as expensive as a Kenwood TS-570D, a rig at more than $2000 or 3000 € all options included can be a great performer but it will allow you to buy a lot of antennas or a linear amplifier too. But if you already have a great spot and the best aerials, e.g a quad cut for each band 10m high (33 ft) installed in a high open field or at sea level, a better receiver may be the way to go. This is also the best choice if you want to replace all your old material (your small RTX, your external filters, and your AT tuner) by a high-end model including all these features from factory. Some QSLs recently received
If you do not want operating in contests or in heavy QRM conditions, or if you are a casual operator and appreciate to ragchewing in local QSOs, the purchase or a high-end transceiver very expensive is probably not the best choice to make. I would go with the Kenwood TS-570D series and similar models. Of course if you have enough money left, or have the opportunity to buy a high-end on secondhand which P.A. has not suffered of bad SWR or a lightning strike, without hesitation you should consider purchasing a Yaesu FT-1000MP Mark-V or one of its challengers, the Ten-Tec ORION, the Icom IC-756PROII (as the model III is now available) or even the Kenwood TS-850S. This latter still uses analog devices – it was designed in the late '80s – but its performances exceed most of recent models, and these radios clearly trade off size for usability. So if you are searching for the best rigs, the transceivers described above count among the finest HF transceivers ever made ! By way of conclusion, I received most of my QSLs using the receiver preamplifier and all possible DSP filters enabled (Noise Reduction, IDBT, VRF, Notch, etc). Without these functions that helped me in extracting weak signals from the hash of the background noise or from the QRM, I had probably missed some DX-peditions and most wanted DX that I worked, sometimes in conditions for the least difficult without a good antenna or technical assistance. In other words, I can no more go without DSP functions, including for the external speaker. Make the good choice. For more information One of the scarce magazine providing a platform for exchanging the latest technical ideas and information is unquestionably the ARRL QEX magazine. As wrote ARRL, "From PSK31 to the future radio design concepts, you will explore it and built it in QEX ! At 64 pages, this bimonthly journal should appeal to those seeking more technical content". QST and CQ Magazine count also among the other majors, not to forget forums and newsgroups. I listed below technical reviews of some transceivers that we discussed the performance above, reviews that I wrote personally(°) or that I downloaded when the document was provided in PDF format free of charge and without restrictions. Unfortunately, other reviews are now available only to ARRL members, the League membership offering valuable benefits to new and experienced amateurs alike. - Manufacturers : Alinco, Collins, Elecraft, Icom, Kenwood, SGC, Ten-Tec, Yaesu - DX Prowess of HF receivers, QEX, Sept-Oct 2002 - Yaesu FT-1000MP Mark-V : Review°, operating manual - Kenwood TS-2000 : Review, operating manual - Icom IC-756PROII : Review, instruction manual - Ten-Tec ORION : Review, operating manual - Kenwood TS-570D : Review°, operating manual - Elecraft K2 : Review, operating manual - Icom IC-706MKIIG : Review, intruction manual
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