Rugged & Ready To Go - The SG-2020 HF Transceiver Review Reprinted with express permission.
The American company SGC Inc. are becoming increasingly active in the Amateur Radio field. Evidence of this is shown by their high profile presentations at the Dayton HamVention in the USA and advertising in Amateur Radio magazines here in Europe. However. even a brief look at SGC equipment will tell even the casual observer that their products were not originally designed for the Amateur Radio market. Obviously styled for professional maritime and Military use. now that their products are being aimed at another specialized sector of the market (Radio amateurs!) SGC have chosen to continue with the general purpose 'Military & Marine' look and clearly state in their promotional literature that the SG-2020 has been designed "for a whole panorama of h.f. users".
In the past I've had the opportunity to review other SGC products. But this time the arrival of the low power SG-2020 h.f. portable transceiver has been awaited with interest because I'm reliably informed that the designer is the same man who originally designed the Index Laboratories QRP Plus transceiver.
The excellent, brim-full of 'character' little QRP Plus (immediately nicknamed 'the rig on a PW office) transceiver was reviewed in the February 1995 PW by John Goodall GOSKR, but eventually became extremely difficult to obtain before the manufacturers ceased production and the designer was recruited by SGC.
Although SGC make no mention of any connection at all between the previous Index Laboratories transceiver and the SG-2020 in the latter's promotional material, the same designer's hand can be seen at work, particularly in the type of filters used. However. SGC make it clear that they are not. and cannot become involved with the original equipment. repairs or any inquiries regarding the original 'QRP Plus' transceiver.
So, without further ado - let's take a look at the SG-2020 transceiver and see how it performed for G3XFD.
Low Power Heavyweight
The SGC-2020 is most certainly a rugged, low power heavyweight rig. Encased in an extremely robust metal (but not waterproof as it uses an ordinary paper cone loudspeaker) housing it looks and feels like a typical miniature military h.f. transceiver. Based on a single conversion superhet design, the receiver uses an i.f. of 6OMHz. The r.f. selectivity is provided by a 7- pole ladder filter at 6OMHz and bi-directional circuitry is used directional in the i.f. and filter chain. Additional filtering is provided at a.f. with switched capacitor filters (see comment later). The manufacturers claim that sensitivity is better than 0.55uV for 1OdB S/N+N with intermodulation better than +18dBm 3rd order intercept. Unusually for today's modern equipment the receiver is provided with a rotary r.f. gain control along with the standard noise blanker. Standard rotary tuning is provided and frequency resolution is 10Hz.
Incorporating a single loop synthesizer. the SG-2020 uses 1OkHz steps with intermediate steps of 1OHz obtained through direct microprocessor control of the reference.
The frequency display is a large easy-to-read L.C.D. type with a separate L.E.D. display for providing S-meter, and relative output indications. Filtering is provided by front panel selected audio frequency band-pass and provides bandwidths from 100Hz to 2.7kHz in 100Hz steps. The audio output from the top mounted loudspeaker is 1W. General coverage receive is provided from 1.8 to 30MHz and coverage of r.f. is also available (400kHz to 1.8MHz) with the broadcast filter by-passed.
Offering a maximum r.f. output of 20W p.e.p. which is front panel adjustable from milliwatts to the fu II output, the transceiver provides s.s.b. and c.w. transmission. The transmitter incorporates r.f. speech processing using a voice operated audio gain device (v.o.g.a.d.) and r.f. clipping.
A built-in electronic keyer is provided and this can be operator adjusted (in IAMBIC 'Mode B') from five to 60w.p.m. I tried the keyer - it works very well indeed but I prefer to use my hand key all my QSOs were achieved using my Kent 'straight' model. There are also 20 memory locations. some of which have been factory pre-set but all of which are user-definable and can be reset at any time by the operator. Power supply input is by an unusual rear-mounted plug arrangement and the accompanying plug (supplied made up on to heavy duty cable by SGC) does not 'lock' into place. As a result it can detach itself quite easily and I found that even the weight of the cable (if it wasn't supported) pulled the plug out on various occasions.
The supplied cable is of a far higher current carrying capability than the pins on the plug and socket arrangement - especially when you bear in mind the SG-2020 is a 20W p.e.p. transceiver. As I've already mentioned, it also 'un-plugs' itself very easily as it does not 'lock'. Definitely a re-think needed here SGC!
On The Air
It's not often I get the chance of a really long review period for a newly-introduced HF transceiver - but in the case of the SG-2020 it was in my shack for close on a month. In that time I had over 300 QSOs - mainly on 7, 14 and 18MHz - and mostly using c.q. With its relatively low r.f. output power quickly found that the transceiver struggles on s.s.b. Audio reports were good but the QRP level output means that QSOs on the bands are a real challenge - which I know some operators prefer!
Personally I think the SG-2020 could be of interest to the dedicated c.w. operator interested in a rugged portable transceiver because in this mode the QRP is no real barrier to DX. Indeed - I worked into various South American countries on 18MHz using only 5W. and in one case managed to work a PY (Brazil) with only 3W! But of course....not many people have beams for 18MHz and my long wire antenna seems to do very well on this band.
The frequency display is exceptionally crisp and clear on the transceiver. but I'm afraid did nor like the L.e.d type of S-meter indicating device. This facility - made up from a series of very bright L.e.d. indicators - is extremely rugged and although perhaps ideal for use in a vehicle - annoyed me very much! Although I should say that Tex Swann G1TEX, Technical Projects Su b-editor (and our photographer) said he liked it! So, this must be a subjective point.
On c.w. I found that my signal reports were always T9 and even though I was often operating the transmitter at well below 3W I often got 579 from the other station who could often be running up to 100W. Yes - C.W. in my opinion is the ideal mode for QRP working and my log book with contacts around the globe on QRP c.w. proves this.
The high i.f. on the SG-2020 provides excellent selectivity for a single conversion superhet and this is further backed by the truly excellent selectable a.f. bandpass filtering. This filtering has to be heard in action to be fully appreciated - it certainly provides the very 'hard edged' extremely sharp filtering needed for the busy QRP frequencies.
Tex Swann G1TEX compared the effect of the filtering with DSP - the main difference being that it was slower because the operator selects the filters. It takes some 'getting used to' but left me thinking that I should consider including switched capacitance filtering of this sort in my next home brew receiver!
Tuning on the SG-2020 proved to be very laborious for me - it's certainly a two-handed job! This is because to select the fastest tuning rate the operator has to press the Fast button while rotating the main tuning control. I found it to be very difficult and frustrating - and even Tex G1TEX found it frustratingly difficult and slow - especially when changing bands. In fact many of the control facilities we take for granted - instantly selectable receiver and transmit RIT for example - are set out in a way that reflects the military and marine operating methods rather than Amateur Radio. However. I really appreciated the variable ref. gain control - the continually adjustable gain often helped me when I was working on busy (and incredibly noisy) frequencies. It's certainly good to have full control!
The general coverage receiver provided on the SG-2020 works well but because of the laborious tuning and band-changing method I didn't really 'tune about' as much as I would have done otherwise. But the receiver copes very well with a.m.. c.w. and s.s.b. transmissions. Listening to h.f. broadcast transmissions on a.m. requires the use of the 'exalted' carrier technique - and the operator can choose to listen to either sideband. I found this to be quite effective and it's something an SG-2020 owner would soon get used to in practice. Listening on the r.f. ('a.m.') band requires the broadcast filter to be by-passed and the operator's manual (which is presented in the usual comprehensive easy-to-read and use SGC style) explains how this can be done by re-locating a jumper wire to an alternate position. Sensitivity on the 400kHz to 1.8MHz band is good and more than adequate for broadcast reception use and it's sensitive enough to receive the slow Morse marine/aeronautical beacons.
So, after the many QSOs and a lot of experience with the SG-2020 does it get my vote:, In short I have to say no - the rig doesn't appeal to me but the quirky design does have some attractions and in an odd way I liked some of the features.
But I honestly don't think it will appeal to many Radio Amateurs. I really think that this robust little transceiver will find its true home as a professional h.f. rig for use as a low power mobile vehicle to vehicle or mobile-to-base radiotelephone operations by relief and emergency organizations. particularly in countries such as Africa. etc. I think the SG-2020's small size and its facilities will also prove of interest to the maritime mobile radio operator. It's extremely well built inside and is presented in a form where it can be conveniently set- up and left for an operator to use PTT radiotelephony.
My thanks go to: Waters & Stenton PLC of
22 Main Road,
Hockley, Essex SS5
409. Tel:(01702) 206835
for the loan of the transceiver which costs £599 plus £6 carriage.
425-746-6310 Fax: 425-746-6384
Email: email@example.comSGC reserves the right to change specifications, release dates and price without notice.