QRZ! Ham Radio 5/QRZ Ham Radio Callsign Database - Volume 5.iso/files/arrl/tis/swrigrev.pt2

Text File | 1994-11-20 | 30.6 KB | 583 lines

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Sangean ATS-803A - 1

Since I was now turned on by SWL'ing, I moved up to what most
people agree is the best all-around radio for this price. Good
points: excellent frequency band coverage (150kHz to 30mHz), fine
tuning, good selectivity, BFO for SSB and CW, many scanning
options, lots of accessories included, good AM and FM reception.
Bad points: way too big to travel with, high battery consumption,
synthesizer noise in background all the time, scanning frequently
skipped lots of   "listenable" stations that I was able to get by
manual tuning (what's   the use in scanning, then?). I found that
adding a longwire antenna   only increased interference and noise
while not improving the set's   scanning sensitivity. Overall, a
fairly good radio for the price...

I have a Sangean ATS803A which I love.  Comments to quote me on
would be that it's an excellent beginner's radio for the price.
Although I've heard that the 818 is the "latest and greatest" in
this price/performance category. I especially love the full
coverage  150kc-30mhz and the (albeit lo tech bfo) SSB
capability.

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Sony ICF-SW20 - 1

I was in dispair when I could not find a decent travel portable
for  under $200. However, I accidentally crossed paths with a
Sony ICF-SW20 on sale (normally $99, on sale for $49.99) at a
local store and had to check it out. It is an analogue set, but
since I got a 30-day return policy on it, what the heck? Good
points: analogue tuning so no problem with confining 5kHz
tuning steps, INCREDIBLE SENSITIVITY - this radio blew the DAK
and Sangean away with the number of stations I picked up, good
selectivity (no fine tuning knob - all you need to do is turn
the tuning knob slowly), tiny size (4"w   x 3"t x 1"d), small
whip antenna (only 18"), addition of Radio Shack   rollup
longwire increased sensitivity even more, great low price (if   I
lose it or its gets destroyed, no problem replacing it), tuning
bands are wider than the major broadcast bands, so you do get
some utilitiy reception as well as WWV, AM and FM are really
sensitive while FM goes from 76mHz to 108mHz so I can pick up
some TV as well.  Bad points: frequencies cover only seven
broadcast bands (I can live with that, though), only monaural
earphone included (however, you can get a $1.39 mono to stereo
headphone plug), no BFO for SSB or CW, no station memories. All
in all, this radio gave me the best price/features/size ratio
of the ones I checked out first-hand. It's a keeper for me!

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Magnavox    3625 - 1

Finally received my Magnavox 3625!  Well, I'm certainly happy I
purchased this little radio.  Sure, it's not top shelf, but it's
suitable for travel purposes and gives adequate SW coverage.

Has these features:
Travel Lock
Alarm (beeps, does not turn on radio)
Sleep Timer
9/10 KHz switch - for world travel
12 hour clock (however, when unit is swith to 9 KHz steps 24 hour
               clock kicks in)
20 presets - 5 for each band FM, AM, SW1, SW2
Dual time
Auto store - this feature allows the radio to automatically find
   the five strongest stations in an area and program them
   into the memory of the FM & AM band.
Back stand
Antenna swivels and rotates
Runs on four AA batteries.

Well, the sensitivity is quite good.  Steps in 1 KHz increments.
No tuning knob but the slew tuning buttons work just fine.  It's
about the size of a paperback book and can be taken anywhere
reasonably well.   No carrying strap, though.  The SW coverage
is limited but it grabs the major broadcasters exceptionally well.
Example:  the 41 meter band is covered from 7100 to 7300.  So if
you want to listen to the BBC on 7325, you're out of luck.

However, I like to listen to the BBC on 12095 or 15070 European
signals during the day that I cangrab when I attach a long wire.
The 3625 can't tune these freqs. but it can grab 15400 (from
africa) WITHOUT a long wire antenna!  I'm pretty impressed.

Bottom line....A GREAT little travel radio for $70.00!  Call a
Magnavox outlet if you are interested.

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Magnavox AE-3805 - 2

Great little digital portable.  Good sensitivity, average
selectivity. Covers MW (in 10 kHz steps only), FM (no stereo),
and SW in two "bands":  3200-7300 kHz and 9500-21750 kHz.  Built-
in timer/clock (12 hour format only), 5 programmable memory
locations per band. Great for travel use.

Purchased from Damark for $49 in May, 1993.

$50 from Damark closeout  --  cheapie category

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Emerson PSW-4010 - 1

Great analog portable.  Good sensitivity and selectivity.  Covers
MW, FM (stereo through headphones), and SW in 8 bands (roughly
split out as 13m, 16m, 19m, 25m, 31m, 41m, 49m, and
60/75/90/120m). An excellent travel portable.
This is the same radio as the Sangean SG-789.

Purchased from DAK for $49 in June, 1988.

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Sony ICF-5900W - 1

Sony ICF-5900W was a good radio in its day, but isn't worth
listing now.

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Icom IC-R70 - 1

I purchased my R70 in early 1983. It came with a scratched plastic
window for the digital display, which the factory replaced. It is
an extremely sensitive receiver. I installed the FM detector board
option, which is highly useful for Sub-Carrier detection from FM
broadcast receivers in conjuction with the R70's ability to tune
below 100khz without a frequency convertor. The so-called PassBand
Tuning (PBT), in actuality an asymmetrical bandwidth narrowing
control, is very mediocre with the factory 455khz filters. Replacing
the 455Khz ceramic SSB filter with a Fox-Tango FT-44 2.4khz 8-pole
crystal filter (equivolent to the ICOM FL-44) makes the passband
filter work as one would want. The AM 455Khz ceramic filter is junk,
and was replaced with a higher quality "4Khz" ceramic filter from
the long-defunct Radio Plus firm. The actual specs for the 4Khz filter
indicate that it is a slightly asymmetrical filter of 5.6Khz bandwidth,
causing a slight degredation of the "highs" (The original spec is
for a 6Khz bandwidth; the 9Mhz AM filter is a 6-pole device). Inclusion
of both replacement 455Khz filters results in a combined shape factor
of much better than 2:1 on AM or SSB. In addition, the RF amplifier
was enabled for AM broadcast band use, and an MOV was placed across
the AC input for protection against voltage transients. [Actually,
a Transorb would be far better in defending against narrow transients.]
For awhile, I replaced the diode AM detector with a Shottkey diode,
but my ears could detect no difference in distortion, and so the
original AM diode was returned to the circuitry. It's been serviced
once by ICOM for an intermittant problem ($150 ouch). There exists
several modifications to enable selection of the 455Khz SSB filter
whilst in AM mode for additional selectivity.

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YORX AM908 - 1

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Drake R8 - 1

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Drake SPR-4 - 1

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Icom R-71A - 2

Eskab & Edvis of Sweden used to offer a Phase-Locked AM (PLAM) detector for
the R-70 and later R-71; they also offer a version for the NRD525. I have
the R71 version. It is a synchronous detector which allows selection of USB
or LSB via the IF filter/BFO offset. The PLAM board phase-locks one of the
R71 local oscillators (I forget which one, probably the BFO) to the AM
carrier. It contains its own product detector. The lock range is not very
large, perhaps +/- 20 Hz. The detector seems to have lower distortion than
the ICOM AM detector.

Compared to ECSSB, aside from the advantages of phase-locking the product
detector BFO, the PLAM unit also lowers the corner-frequency of ICOM's
low-pass audio filter, giving better bass response than normal SSB mode on
the R71. I find that this improves the intelligibility of the signal.

The PLAM board piggybacks in the mounting area for the ICOM FM option
board; both can coexist. Installation is somewhat difficult, as it involves
connecting over a dozen wires to various boards in the R71.

Eskab & Edvis also offered a 4 KHz 2nd IF crystal filter for the R71. This
installs fairly easily in place of the narrow CW filter. It is very much
better than the stock ICOM 6 kHz bandwidth, which is wide-open until it
hits at cheap ceramic filter in the 3rd (455 kHz) IF.

I don't know if Eskab & Edvis still offer the R-71 PLAM and 4 kHz filter.
They used to advertise in the WRTH.

Regarding other options: I believe Sherwood Engineering offers an outboard
synchronous detector for the R71 as well as other receivers. The Kiwa MAP
unit should also be adaptable to the R71.

Also, Dom Moman of Shortwave Horizons publishes a modification manual,
which details mods like enabling the preamp on MW, true pass-band tuning,
sub-10 Hz RIT, etc.

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Kenwood R-2000 - 1

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Kenwood R-5000 - 1

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Kenwood TS-450-1

I know it's not a reciever, but since it has general coverage,I decided to
put it in here.  The TS-450S ,An amateur transciever that costs little more
than a R-5000, and if you have your ham ticket or are thinking about getting
it, may be worth checking out if you are in the market for a new toy. I'd
be willing to bet the replacement for the 5000 will look just like the 450,
just like the 5000 looks like the 450's predacessor, the TS440S.  First
thing it is EXACTLY the same size as the 5000/440.  Unlike the 5000/440,
it has an LCD display that is unlike any other I've ever seen.  It is
almost too bright!  The brightness cannot be adjusted, unfortunatly.  The
450 recieves in all the standard modes except for fax. It has a "normal"
keypad unlike the 5000 and the aggravating CW that is produce when a major
button is pressed can be silenced by a simple menu, you dont have to cut a
wire like the 5000he S-Meter is a bar-graph type that I like but some
people dont.  It also has an Audio meter function that kin baffles me.
I still dont know what use it is, but it looks nice!  Probably the most
notable thing you will observe when using the 450 is the QUIET!  It is
so quiet,it seems strange the first couple of times you use it.  The AGC
is non-defeatable and has a fast/slow toggle.  It is the strangest and
slowest AGC I've ever seen, on slow the S-Meter just sits there and then
SLOWLY goes down.  On fast, it just isn't quite so slow.  It seems to work
ok,but is really odd.  The stock filter for AM is a mile wide but you can
add the YK88 AM filter but you wll lose the open slot for the 8.83 ssb
filter.  I'm not sure, but the 450 seems to have the same stock am filter
the 5000 has.  On SSB,it uses one of the better Murata ceramic filters and
is ok but the optional SSB filters are highly recommended.  The audio is
FANTASTIC on all modes and if you put one of the minimus speakers from
Radio Shack on it, you will like it a lot.  Dont bother with the Kenwood
speakers, the one that goes with the 450 is not too good and is expensive
too!  The ergonomics are pretty good, except for the tuning knob, yes
like all the recent vintage Kenwood rigs, IT DOESN'T HAVE A FINGER HOLE!!
Why does Kenwood insist on putting these awful knobs on all the rigs they
have made lately!  All in all, it is a very good riever in almost all
respects,and since it only costs about $100 more than a 5000, it is worth a
look and as a bonus, the recieve coverage goes up to 40 mhz!If you are into
low band scanning, you will hear things on the 450 you never knew existed on
your scanner.  If you can swing the 450's sister model the TS690,you can
recieve all the way to 60 mhz.  When the 5000 is put out to pasture, if it's
replacement is the 450 without the transmitter, it will be very tough
competition for the other makes.  All it needs is Sync.detection and you
really couldn't ask for much more.

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  Japan Radio Company NRD-515

THE all time most user-friendly recieveof recent vintagHas PBT,analog
fine tune,four I.F.bandwiths,AM,LSB,USB,and RTTY modes.There is no squelch
but it really doesnt matter much.Of all the recievers I have owned, or ad
over here to play with, it is the most sensitive in the SSB modeI have the
standard 6 and 2.4 khz filters, and th600 and 300 hz filters whitch are great
for RTTY or CW (if you are truly desparate!) The "protection" diodes have
been removed due to intermod from a local AM station. The reciever's case,
front and back panels are made of Aluminum, no plastic to crack on the 515!
The audio in AM is very bad, almost as bad as the Icom R-71a, but in a
different way.  The audio is "fuzzy" out of the speaker jack, but not too
bad out of the record jack but still a little "fuzzy".  In the SSB modes,
the audio is pretty clear and doesn't fatigue me like the Icom dos far as
thergonomics goes, it's almost prefect!  All the knobs are the right size,
the tuning knob is large and has a nice deep finger hole (Kenwood, are you
listening???).  The S-meter is big and easily seen across the room.
Dynamic range is very good after the diodes have been clipped (a one
minute operation).  The filters all are good quality and have good shape
factors.This was the first "affordable" rig that had a memory option that
was worth something with 24 or 96 channels available.
The NDH-518 I have (96 ch.) is also made totally out of cast and sheet
aluminum and matches the 515's styling. It stores frequency only,
unfortunatly, due to the year it was designed Im guessing. There are lots
of these recievers floating around on the used market for about $600 or so.
Universal seems to have a lot of them passing through the store.

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Japan Radio Company NRD-525 - 1

This is a great reciever,marred only by bad audio and a hiss that will drive
you bonkers if you have good hearing and  a speaker that can put out the
highs.
I have had two of these,the first I traded for a sateite setup,and the one I
have now.The newer reciever has mucbetter audio then the first one and less
hiss too.Ergonomics are very good MUCH,MUCH better than the Drake R-8.
(IMHO,the Drake is seriously overrated and all the stuff about made in
the U.S.A.is kind of funny cause a LOT of the innards are MADE IN JAPAN!!!)
Oh well, back to the 525,if you are into AM,it's probably not the reciever
for you, but in all the other modes,it is one of the best consumer grade
recievers ever made. Performance in all modes is basically excellent except
for the audio problem,and stability is rock solid.  JRC has only cut a few
corners compared to the 515, probably the ultimate in construction for
consumer recievers. The case is made of very thin sheet metal and the front
panel is plastic. The keys fit loose in the keypad but work ok. The display
has four brightness levels and is very easily read from across the room. The
S-Meter is "digital" and is a floating vertical bar segment that seems to be
yellow on some samples, and green on some others.It is sort of "spastic"and
twitched a lot on the first one I had,but not as much on the seconone. The
first 525 I had would "click" on strong AM signals,but the new one doesn't.
The main tuning knob spins very smoothly and has a nice finger hole.
(KENWOOD,WHY DONT YOU LISTEN!!) All in all, a great reciever.

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Japan Radio Company NRD-535D - 1

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Yaesu FRG-100 - 1

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Panasonic RFB-65L - 2

$220 from Universal, EEB, etc. -- my main set, an excellent
portable, many features, nice construction and details.

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Sony SW-55 - 2

This is my principal radio at the present time (I also have the
Sony ICF-SW33 and the Sony 7601).  This rig is an extremely
sophisticated piece of equipment.  I especially like the fact
that you can store up to 125 frequencies on 25 electronic pages
that can be named as you wish (by country). Once programed this
is very convenient.  The two filter selections are well chosen
(much better than the stock Sony 2010 filters).  My use the radio
to copy WEFAX  with  excellent results attests to its stability
(and that it receives USB and LSB).

The versatile timer/alarm and tape remote feature allow
automatic recording with certain tape recorders (Sony and others)
of up to five times and frequencies in a 24 hour period.  I use
this feature all of the time.  Audio (stereo on FM) qualitity for
a portable is very good; better I believe than the stock 2010
although  as with the 2010, it is improved with a set of external
speakers.

Unlike the 2010, the SW55 does not have synchronous detection.
That's too bad because I believe that if it had this feature it
would blow away
tition.  As it stands it is an excellent radio.  Most
interference can be eliminated with the narrow filter or moving
away from the interference a bit (the radio is tunable in steps
of  0.1 kHz)  so the lack of sd is not critical.  I really
believe that Sony did not include it because it would have then
had a very negative impact on sales of the SW77.

Would I buy this radio again. You bet!  The only problem I've had
in the year an owned it is that the lettering has worn off the 1, 5, 0 and
EXE keys on the keypad.  That should not happen on a $300.00 radio!


I just got a SW-55 for Christmas and find it to be an outstanding radio.
Now that I've said that, you should know that I am new to all of this
"DX-ing" (is that how you say it?).  However, I can tell you that it's
reception with the built-in antenna and with the included auxiliary antenna
is very good.  I found that the radio comes pre-programmed with a number of
stations (BBC, Radio Moscow, etc.) and they come in great.

As for your questions, I've found the speaker in the SW-55 to be very high
quality, delivering plenty of volume and good sound.  There are several
"tone" switches (news vs. music setting, etc.) that enhance the reception
and its sound.  And, the unit is packaged well for travel.

The radio itself has several nice features (I don't know how they compare to
other radios since I didn't comparison shop).  There are several output jacks
that make it easy to connect to external speakers, tape recorders, headphones,
etc.  There are local/long distance antenna settings.  There are lots of ways
to set and look at the time (local, UTC, Daylight savings, etc.)  There are
alarms and sleep settings (for on the road).

The tuning portion is quite nice.  The radio of course offers digital tuning
(punching numbers in to get to a freq.).  But I find that I often use the
"analog" tuning dial as well to either fine tune a station or to see what
else is out there.

Best of all, the unit is packaged well.  As a new user, I have enjoyed the
little things Sony has done to make this experience a good one for the new
user.  Everything from the documentation to the carrying case has made it
quick and easy for me to start listening to short wave.  Included is a book
that is a publishing of all the various countries broadcasting, with their
freqs and times.  (I gather that these things change quite a bit, but I
presume that Sony updates it often)

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Philips AE3905 - 1

In short, in my experience, the AE3905 is no real great shakes.
It looks neat as hell, and marks its owner as a man of taste and
distinction with more money than brains (like I said, *I* have
one). Its shortwave performance is mediocre.  Using this in a
hotel last February, I found that attaching the included reel
antenna caused the radio to overload fairly badly.  The batteries
don't last very long.  The filters included are fair, but you
still get a fair amount of interference from adjacent stations
(not as bad as some small portables, but not good).  I certainly
wouldn't want to use this as my primary radio.  For portability,
it's fantastic.  I can listen to the BBC or VoA anywhere.  The
radio fits in my shirt pocket, although reception in my pocket
isn't all that good. In short, the radio isn't worth what Philips
charges for it, but if you've got more money than you know what
to do with and a desire to have a flashy looking toy, it'll do.
The radio has only recently been available in small quantities in
the U.S., and appears to have been discontinued in Europe.  I got
a reconditioned copy for $179 from the Magnavox factory outlet in
Kentucky.  Universal lists the radio in their catalog for
something like $250 new if I recall correctly.  You're not likely
to find it anywhere else.

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WATKINS-JOHNSON HF-1000 HF RECEIVER

I will be doing a lot of comparisons to my other receiver, an NRD-525.
To give a basis for comparison, the NRD-525 has been upgraded by the
following modifications:

   ESKA PLAM board with four added filters following the IF strip
   Installation of ESKA Aux filter in the NRD Aux position
   Installation of the JRC 1.8 KHz filter in the Narrow position
   Replacement of RF chokes on the filter board with shielded units
   ESKA agc modification

These modifications have improved the shape factor on the NRD's filters
from an average of 2.0:1 to 1.7:1 (60:6 dB).  The ultimate rejection has
improved from about -60 dB to -75 dB.  These modifications are noticeable
in on the air listening tests.  The NRD hiss has been removed.

About two months ago, I bought another receiver, a Watkins-Johnson HF-1000.
I didn't really think this receiver would be much better than the NRD, and
I intended to return it if this was the case.  I was wrong.  The Watkins-
Johnson receiver is clearly superior to the NRD in on the air listening
tests, almost in every case.  In rare cases it is a tie.  The comparisons
are done using an A/B switch that switches both the RF and audio lines so
that comparisons can be made quickly on the same signal.  Comparisons
were all done in ECSS mode with the receiver settings made as close as
possible to each other.

I also did some bench testing of both receivers, and the numbers that the
tests give are not all that much different for both receivers, with the
exception of filter shape factor.  The HF-1000 shape factors run about
1.1:1 (60:6 dB).  This does not explain the main difference between the
comparisons, however.  The HF-1000 seems to be superior in pulling out weak
signals.  I have heard many signals that are muddled and hard to understand
on the NRD-525 sound sharp and clear on the HF-1000.  Several other points:

    AGC: The digitally processed AGC on the HF-1000 is far superior to the
      analog AGC on the NRD, even with the ESKA kit installed.
    Notch filter:  Again, the digital IF notch filter is superior.
    Audio:  The NRD audio has always sounded low frequency and mushy; audio
      on the HF-1000 is crisp and clear.  This is an important item.
    Operating:  I like the controls on the HF-1000.  They are flexible, yet
      easy to use.  The set is a pleasure to operate.
    Synthesizer spikes:  The NRD has a synthesizer spike every 100 KHz.
      While these are not all that strong, some of them fall on inconvenient
      frequencies, like the propagation beacons on 14100 KHz.  There are
      a few spikes on the HF-1000 at even 2 MHz points.

The only shortcomings in the HF-1000 I've noticed are the lack of synchronous
detection (this is supposed to be sent out as an upgrade chip later), and
IF passband tuning would be useful in the SSB modes.  It is present in CW.

As you have probably guessed, I'm real happy with this receiver.  I think
it will be the last one I will have to buy for quite a while.

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AR3000 - 1 (More Info is Available by e-mail from ([e-mail])

My general impression, is that this is anyhow a very good apparate. It
offers continuous coverage 0.1 : 2036 Mhz, all mode, RS232 interfacing,
quite good operating commands, triple conversion, 400 memories; it is
very compact (small tabletop, 1.2 Kg.), semi-portable; its 13 auto-selected
front-end band filters reduce to some extent unavoidable intermodulation. In
general, this set offers a self contained and very well balanced compromise
of a lot of different demanding features, but will show its best when fully
interfaced.

Its price, here in Italy, has been varying greatly during the years.
Therefore I cannot say how it really competes with the choice of HF
receiver + scanner setup. It is still unclear to me how far is the AR3000
from dedicated traffic receivers.

I'm finding a number of defects and "whish it was" that I'm going
to list (I would like to hear comments about), but perhaps I'm
just pretending too much from a receiver in which something had
to be traded off between versatility and performance. Please note
that I have a 4 years old AR3000; some defects could have been amelio-
rated in the 3000A, or may eventually be specific of my unit.

Hardware limits:
----------------

-AM selectivity is mediocre (approx 10 khz bandwidth). I feel the lack
 of a variable Am bandwidth. SWL in crowded bands is too often spoiled by
 the 5Khz whistle. Thinking it was a problem of i.f. detuning, I once
 sent it to the service to have it retuned, but with no perceivable gain.

-In AM I do experience blocking. A strong transmitter mutes any weaker
 adjacent signal lying some -+30 khz apart. I suspect this may be rather
 a problem of AGC voltage (see below on squelch), because the feedback
 signal is obtained from the previous to the last i.f. stage, which may
 have a larger than necessary (for AM) bandwidth.

-The squelch control (essential in search mode) is not very functional.
 On my set almost everything passes for knob positions below .3 and
 only >S6 passes when I increase to .5. It may be a problem of adjustment,
 but also reflect the inaccurate behaviour of the S-meter, which (I have
 no measurements to support) seems not properly logarithmic. I have
 the impression that weak signals give a high S readout when close to
 stronger ones, because the S-meter averages on a larger bandwidth than
 the demodulator.
 Also, the squelch just mutes the a.f. output, but not the line out signal.

-The internal speaker fidelity is scarce. No tone controls exist. Clarity
 improves a lot when connected to an external speaker or lineout. No
 noise reduction circuitry is present. External audio equalization does
 a lot, but of course is not the cure for low selectivity.

-There is no i.f. direct output for say a spectrum analyzer or a different
 demodulator (say wide band AM for satellite or TV, stereo FM decoder,
 sinchro SB AM decoder). A modify could be to buffer it to a backpanel
 jack.

-Intermodulation IS present. I live very close to power MW transmitter,
 and in the times they're on the whole band .5 : 2.5 Mhz is unusable,
 with crosstalk on every possible combination of transmitter frequencies.
 At evening I sometimes hear sw bc stations crosstalks on 20 : 30 Mhz, even
 with a short random wire antenna. However, I don't hear crosstalk due
 to FM transmitters, which are also close to my place. The 13 front
 end filters seem to do their job, since strong signals don't cause
 crosstalk out of their respective preselector bands.

-I'm not very satisfied with the small and clicking rotary tuning control.
 In the AR3000a it has been replaced with a (I guess optically encoded)
 smooth one. I would rather appreciate a jog-shuttle like the one on VCRs,
 and the mod itself seems quite easy too.
 The tuning is however digital, and stepping frequency causes clicks, which
 eventually trigger the squelch threshold during search. The final a.f. is
 briefly muted while stepping, but I prefer the line-out signal which is
 unaffected and thus has a faster response.

-There is a single antenna input for the entire range. I think this however
 is correct, because whichever choice on different antennas is entirely
 dependent on the user setup, and should be rather left to an externally
 programmed antenna switch.

-Some digital RFI is generated, expecially in the high HF and low VHF. A
 real antenna connected with a shielded cable and a good earth however
 wash it out.

-Some small change in sensivity and background noise can be perceived when
 passing across one of the 13 band boundaries (by the way, they are 0.1-0.5,
 0.5-2.5, 2.5-10, 10-30, 30-50, 50-108, 108-136, 136-174, 174-224, 224-335,
 335-500, 500-940, 940-2036 Mhz), but this is unavoidable, and also due to
 the change of the superetherodyne scheme.

Software limitations:
-----------------------

-Scanning is already very versatile for such a small machine. However, auto
 memory storage of catched frequencies was forgotten. Also, the oddities in
 the S-metering (see above) impose manual choice when scanning non regularly
 channellized bands.

-There is a priority channel lookup feature, but the attention threshold has
 to be the current squelch position. Apparently (see
 //ftp.funet.fi/pub/dx/receivers/mods/aor300.mod) in the 3000a
 a programmable lookup time was implemented, but it is not present on
 the 3000.

-The mode and the tuning step change are set with several keystrokes. I feel
 it quite tricky, expecially considering that I generally have to switch
 quickly between 50 Hz/SSB, 500Hz/Am, 1.25 Khz/nfm, 50 Khz/WFM. The step
 x10 command is very useful, but not enough.

Since the S-meter signal is output on the RS232, and the unit may be fully
remotely commanded, all this limits can be cleverly threspassed by an external
control software, thought.

I have experienced problems with the 232 interface. The cpu goes crazy very
easily when the connector is plugged in/out, unless the "remote" switch on
pin 7 is previously operated. This is (I understand) the reason why it was
added on the 3000a. When the cpu goes on the moon, one generally has to open
the set and to push the reset button (backside of the keyboard), losing all
the memories.

*eof