Icom 756 Pro Iii Serial Numbers
.HF/50MHz ALL MODE TRANSCEIVER iC-756pro S-14110XZ-C1-q June. READ the instructions of test equipment throughly before connecting a test equipment to the transceiver. Icom, Icom Inc.
ICOM 756 and 756PROW8WWV - ICOM 756 and756PRO (and PRO II)Greg OrdyLast Update:Wednesday, February 26, 2003 05:59 PMI decided to replace my ICOM 756 with a 756PRO. This gave me anopportunity to compare both radios side-by-side. This page contains my observations.Additional 756PRO information can be found on the pages maintained by, the ICOM reflector (mailinglist) at, the and ofcourse, the site.
If you have any of yourown observations, please email me, and I will add them to the list if appropriate.ICOM introduced the PRO II radio in the second half of 2001. As of thiswriting, the radio is still quite new, and comments and observations are just starting toemerge. A few of my observations are contained at the.Because I am comparing two radios here, it may appear as if one is goodand one is bad. I really do not want to give the impression that either radio is bad. Infact, given the cost difference between the two radios, I think that both are well worththeir respective prices.
For me, I decided that the upgrade cost made sense because of theequivalent cost of the filters necessary to turn a 756 into a PRO. Of course this is noteven possible because the 756 has a single filter slot at each IF frequency. But if therewere more slots, it seems as if I would need to add 6 or so filters to be able to get theSSB and CW selectivity choices I would like. At $100 to $200 (USD) per filter, the costdifference between the radios evaporates. On top of that, there is the color display and anumber of other enhancements. So, for me, spending the extra money made sense.Topics.I think we have all learned that S meters are, at best, relative signalstrength indicators. S Units are not a standard.
S meters are not calibrated against anabsolute signal strength reference. Still, they are all we have to measure signals, andthey are often quoted.With two radios it's very easy to compare how each reports signalstrength.On both radios, the difference between S8 and S9 appears to be 6 dB, atypical value. Above S9, the meter readings are fairly accurate, which is to say thatmeter markings track real relative decibel changes.
Below S8, both meters becomesincreasingly more sensitive. The difference between S1 and S2 may be as little as onedecibel or two.I also found what I call a tracking difference between the two radios. Themismatch was the greatest on 20 meters, where the 756 read the same signal as 8 dBstronger on its meter. The difference was about 5 dB on 40 and 15 meters, again the 756reported a higher value. On the other bands, the two radios basically tracked. Their Smeters indicated the same strength for the same test signal.The S meter on the PRO is also what I would call sluggish. The Smeter on the 756 seems to follow syllables in words, and the dits and dahs of CW.
Themeter on the PRO moves more slowly, regardless of AGC speed.Finally, there appears to be no adjustment on either radio for S metercalibration. The meter itself, which reports several different qualities, is driven from amicroprocessor. The meter readings are not the result of analog signals changing, they arethe result of a numeric computation.
What you see is what you get.Since I made my first comparisons, I have made a closer look at the SMeter. That information is on, and if you havea 756PRO, you might want to check out my software.I have written about ICOM radios and microphones on another. With the 756, I found it difficult to drive thetransmitter to full output with a dynamic microphone element. I had to use an electretcondenser element (or a dynamic element with a pre-amp). The PRO appears to have moreavailable microphone input gain, and I can drive it fully with both dynamic and electretcondenser elements.Page 12 of the PRO Instruction Manual depicts the back panel of the radio.The PRO, and not the 756, has an additional jack, the Transverter Jack. This jack has beenadded directly next to the Receive Antenna Connector. Both are phono (RCA) jacks.
Thedocumentation for the PRO incorrectly reverses the two jacks, Transverter and ReceiveAntenna. This mistake is repeated every time that either jack is shown in the manual. Thelabeling on the back panel of the radio is correct.The PRO has a transverter I/O jack, the 756 does not. The transverterfunction is activated by placing a 2 to 13.8 VDC signal to pin 6 of the ACC2 jack. Whenthis is done, the radio receives through the transverter jack, and transmits a -20 dBmsignal on the same jack.This observation applies to both radios. The front panel has a NB (noiseblanker) button, which activates the noise blanker function.
There are no additionaladjustments. Many people report that the noise blanker does nothing and is a uselesscontrol.
My observation is that the control is effective if you consider it to be an ignitionnoise blanker. From time to time, I have ignition (spark plug) noise near the house.This is usually due to a chain saw or air compressor. The noise blanker is very effectivein removing this type of noise. For general atmospheric noise, however, the control doesdo very little. I suspect that ICOM believes that the NR (noise reduction) control shouldbe used to deal with that class of noise.The spectrum analyzer on the PRO is much more sensitive than the one onthe 756. Signals really jump out on the PRO, whereas the scope can be nearly a flat lineon the 756, especially on the upper bands when the band is quiet.
At first, the differencewas so great that I thought that there must be a change in the fundamental computation ofthe scope data, in addition to an increase in scope gain. But after trying to carefullywatch both scopes at once while changing the scope attenuator on the PRO, I am of theopinion that both scopes are the same, except that the PRO scope has about 15 dB moregain. The PRO scope does have several scope attenuation settings which can be used ifdesired.Both scopes are influenced by the pre-amp setting. The scope is after thepre-amp, so increasing the pre-amp gain will increase the scope gain. I found myself oftenincreasing the pre-amp gain on the 756 just to make the scope more responsive.
With theadded gain in the PRO, I only use the pre-amp to improve the audio, not the scope.The PRO also has a two-color mode that uses a muted second color toindicate the maximum signal at each frequency (while the first color follows the signal).When you turn the VFO, the display starts to recompute the maximum signals. While this isthe factory default setting, I find it to be annoying, and I turned it off as soon as Ifigured out how to do it. I suspect that this was done to give some sex-appeal to thecolor display. I don't find it useful, however.Much has been written and spoken about the so-called audio distortion onthe PRO.
Here's my opinion.Using the small built-in speaker is not a good way to listen to the radio.An external speaker, or better yet, an external amplifier and speaker connected to theaudio out (not the speaker out) is much better. I have all three. The internal speaker, anexternal speaker, and I feed the audio out into my computer sound blaster card where I canroute it to some good quality multimedia speakers. As the speaker gets better, the PROaudio quality also gets better. That's hardly shocking. The same can be said for the 756.Still, there is what I would call a brittle quality to the PROsound.
At the extreme, it's harsh. As best as I can guess, it's due to the digital IF. Insome sense, it's a signature of such a large amount of digital processing. Infact, I think that the 756 has a more pleasing sound than the PRO. I would much ratherlisten to a fat and rich AM broadcast station on the 756 than on the PRO.
The PRO filtersare claimed to be very sharp (shape factor), and this will color the audio as well,especially when there are a number signals surrounding the desired signal. I would not besurprised if this phenomena was similar to what happened when CDs were introduced in theearly 1980's. At first they sounded crisp, brittle, and sterile compared to analog medium,which was warm, lush and full.I find the CW sound to be the most interesting, especially with using anarrow filter setting.
On the 756 (350 Hz filter, 9MHz IF), it sounds like you arelistening to a narrow wedge of spectrum. Narrow but natural. When a signal appears, youcan hear the character of the transmitter quite clearly.
On the PRO, with the same filterwidth, it's as if you are listening to a computer reenactment of the spectrum. Of coursethat's what it is. Narrow but artificial. When a signal appears, it's more of asynthesized replica sound as opposed to the underlying transmitter sound.On several occasions I have looked for weak CW signals and tuned bothradios to the same frequency.
It seems as if both radios have similar sensitivity. If youcan hear it on one radio, you can hear it on the other. The difference I found was that Icould hear the dits and dahs more clearly on the PRO than on the 756. Especially withhigher speed CW, very weak signals blur together on the 756. Even if you can hear thesignal, you can't copy the text. With the PRO, it is often possible to hear and understandthe CW. The edges of the dits and dahs are sharper and cleaner.In summary, and when comparing just these two radios, I find the 756 to bewarmer and smoother, whereas the PRO is colder and more brittle.
It does seem, however,that the signals from the PRO are somewhat more intelligible and understandable. It'scommunication, not HI-FI.Both radios feature an auto notch which is in the audio chain, after theAGC. While they effectively remove carrier tones from the audio signal, the impact of the(usually loud) carrier on the receiver front-end is unchanged, meaning that the receivergain is reduced. This often makes the desired signal undetectable. This is no more thanthe common AF DSP notch.The PRO, however, has an additional manual notch which is implemented atthe IF DSP level, and is before or at least within the AGC loop. Of all of the features onthis radio, this is the one feature that I would call amazing.
The notch is quitenarrow, and one must adjust the knob carefully. But, when you hit the frequency, the tonegoes away, and the S meter drops as gain is restored to the front-end. The desired signalagain appears.It is possible on the PRO to read the S meter value from the computer(serial) interface. This is not possible on the 756.
My software works with the PRO.Both radios feature what ICOM calls triple band stacking registers.What that means is that the radio memorizes three different frequency/mode combinationsfor each band. You cycle through the choices by pressing the same band button multipletimes. This lets you store, for example, a favorite CW frequency, digital frequency, andSSB frequency. Just keep pressing the same button until you get to the one you want.One of the bands is the so-called General Coverage band. I wouldlike to program my favorite local AM broadcast station, 10 MHz WWV, and 15 MHz WWV. Forsome reason, neither radio will allow me to get those three frequencies on the generalband registers. I think this all comes down to the definition of the word band.We know what that means in the amateur case, but in the general case, it is conceptuallythe entire receiver range.
But as you turn the dial across the receiver range, in thegeneral band, you do hear, from time to time, beeps, which normally signify band edges.They may correspond to the common shortwave broadcast bands, but I have not verified that.In any case, these beeps do appear to trap a register in a band. So, somefrequency combinations do not appear possible.
This is a very small point, and I doubt ifthis is a bug, as opposed to just the way that it works. But, it is not documented, anddoesn't make obvious sense (to me!).The 756 has audio speech compression, whereas the PRO as RF compression.Only the PRO has a meter position that indicates the compression amount. The manualsuggests between 10 and 20 dB of compression. I have found that much lower settings areeffective without sounding like a typical compressor (jet engine in the shack). It shouldbe remembered that I use a headset microphone that is very close to my mouth.The PRO has a built-in voice recorder.
The 756 does not. Note, however,the PRO voice recorder is not very useful. On both receive and transmit you can record upto 4 different segments, each up to 15 seconds long. The received segments can only beplayed on the speaker, and the transmit segments can only be transmitted and reviewed onthe speaker. Two additional capabilities would have made the recorder a much more usefulfeature. First, the ability to play back received audio on the transmitter (let yourfriends hear how they sound at your place), and the ability to trigger the transmitmessages from the computer interface (to be done so by logging software).
Without thesefeatures, the voice recorder is basically a gimmick. The Yaesu FT-920 has about the sameproblems.Another great variation would be to allow the voice recorder to recordcontinuously, and be able to replay the last 15 seconds on command. I would really likethis for capturing DX exchanges, where I would like to make sure that my call was copiedcorrectly. Of course you never know that the DX is coming back to you until it's too lateto hit the record button, so you really can't start recording on cue. It's much better tobe continuously record, then stop recording after the important part of the exchange.This is one control that does not impress me very much on either radio.The function certainly seems nearly identical on both radios. It appears as if the intentof this control is to remove atmospheric (and other random) noise from a desired signal.As you increase the reduction value, the noise is indeed scrubbed away, but so is thereadability of the signal, especially on SSB. The control changes the signal/noise sound,but to me, it never really improves it.
I find the control most useful on low settings,around 9:00 o'clock. This is helpful for taking the edge of noise bursts while ragchewing.I certainly don't see how this control could be useful in weak-signal work.I looked for a number of what I would call weak signals. Theseincluded CW signals on an otherwise dead upper band (no background noise at all), and weakSSB signals in the 75 meter DX window (little background noise). In all cases, the radioshad very similar sensitivities. If I had to pick the more sensitive radio, however, itwould be the 756. Please note that I conducted my tests with both pre-amps off. Since thepre-amps appear to add the same amount of gain, I do not believe that the pre-amps wouldchange my comparison.Given the brittle sound of the PRO DSP, and coupled with the slight edgein sensitivity going to the 756, and assuming the same filter bandwidth in both radios, Iwould prefer the 756 (receiver) over the PRO.
It's close, but the warm and lush analog 756is very appealing. The IF DSP needs to offer just a little more to truly pull ahead of theestablished analog technology.The conflict is that the 756 has a single filter position available ateach IF (9 MHz and 455 KHz). This means that it is impossible to get as many filterchoices as I would like. As a compromise, I would put the 350 Hz filter at the 9 MHz IF,and a 250 Hz filter at the 455 KHz slot. The default SSB filters would be used. In myopinion, this would give the 756 SSB, wide CW, narrow CW, and RTTY filtering. It would bea very appealing configuration.The primary appeal of the PRO is the large number of filter width choices.I believe the number is over 40.
Given the number of free filter slots in the 756 (see thecomments), the PRO hassubstantially more filter choices. The way that the radio is set up, it is convenient tothink of three filter settings per mode. Each of these settings can be changed, but Ifound myself picking my three favorite settings and then not changing them that much.On SSB, my most common filter settings are 2.8, 2.4, and 1.8 KHz. Thesevalues are close to the factory defaults. I find myself lowering the center frequency,however, in order to better match the typical male voice, and to reduce the high end hiss.The filter selection does make quite a bit of difference. Normally, I'll use a 2.4 KHzfilter for DXing, and 2.8 KHz for ragchewing. When the local signals are good, it's niceto be able to crank up the bandwidth and get a fatter sound, approaching AM or FM.
Thereal value of the filters comes in when an interfering signal enters the passband. On manyoccasions I have had hash and garbage really eat into the desired signal. By going to 1.8KHz, the interference is clipped off. Coupled with the manual notch to remove carriertones, it's a powerful combination. One can go below 1.8 KHz when necessary. I do findmyself reaching for the filter adjustments and it's great to be able to adjust centerfrequency and width. Very flexible and powerful.
I no longer accept adjacentchannel interference, I try to get rid of it. It can usually be done.On CW, my most common filter settings are 1.2 KHz, 350 Hz, and 100 Hz. Ithink I use the 350 Hz setting since that's the filter width I have in the 756, and I havewanted to duplicate that in the PRO (for comparison tests). I thought at first that Iwould always use a very narrow filter.
But in practice, I like to start off wide, and gonarrower as needed. In some sense, the wider CW filters are used for spotting,that is finding activity. Here's where the more sensitive spectrum scope on the PRO isvery nice. When using a narrow filter (100 Hz, for example), it is easy to simply misssignals. The scope will show me that a signal is there, and I rock the VFO back and forthin order to find it. When you get very narrow, tuning can be critical.
That may be thetime to turn on the RIT, in order to make sure that the transmit frequency does notchange.On SSB transmit, there are three selectable widths. It's hard tounderstand why one would leave the wide setting. I should explain that I havenever been a fan of the classic narrow bandwidth contest audio - it's no fun tolisten to for any length of time. I do admit that it does have its moments. I have had thefollowing scenario happen more than once. I will be one of many stations calling some rareDX.
After perhaps a dozen calls, I will finally realize that under the existingconditions, my signal strength is nothing special, I am one of many. I'll then (hopefully)remember to narrow my transmit audio bandwidth. In many cases, I've made the contact onthe next call or two. I can only believe that the additional punch made thedifference.I wish that these radios had a carrier offset adjustment for SSBtransmit, like on some Yaesu radios.After over 30 years on HF, I finally tried 6 meters in the summer of 2000,with the sunspot cycle near its peak. It was quite a bit of fun. Both radios support 6meter operation.
What I wanted to share on this page was the high value of the spectrumscope on this band. When an opening occurs, the scope makes it very easy to find theactivity. This is especially true on SSB, where stations tend to gather at 5 KHz spacingon and above 50.125 MHz. It's easy to keep track of all of the activity on the band.Apparently the phrase Twin Passband Tuning has been an ICOMsignature on a number of radios.
It is the ability to exploit IF shift at two different IFfrequencies from one set of concentric tuning knobs. The effect it creates is the abilityto both modify (in width) and shift the effective passband. The 756 even presented alittle picture of the virtual passband, which changed as you adjusted the knobs. ICOM hasretained the Twin Passband Tuning terminology on the PRO, and I don't think itmakes much sense.First of all, the phrase is technically incorrect since one is no longershifting twin passbands. All of the adjustments are within one IF within the DSP. Ofcourse this is actually a simplification of the way to think about filters, since now wehave what we always wanted, which is to talk about the filter in terms of filter bandwidthand filter center frequency.
In my opinion, the PRO knobs should have been labeledBandwidth and Center, as opposed to Twin PBT. I think they didn't want to scarepeople away who might think that their big feature was removed. It isn't removed - it'sbetter, but they used the old language. This is just a small user-interfaceissue. If you go into the filter adjustment mode on the PRO, you have a complete pictureshowing the filter width, starting frequency, center frequency, and top frequency.The 756 has a feature called APF, Audio Peak Filter. It really is nothingmore than an audio filter used with CW. It has 3 selectable bandwidths, 80, 160, and 320Hz.
The center frequency is also adjustable to match your favorite CW pitch. This featureis not on the PRO, and it does not need it, since one can create an IF filter which is asnarrow as 50 Hz. An IF filter should always be better than an audio filter.The 756 lets you select one of three (slow, mid, fast) AGC time constantson non-FM modes. The PRO gives you the same three selections, but the underlying timeconstants can be user specified in a configuration table.
It seems like there ismore to adjust here than one would ever need.Much has been written and said about the so-called intermodproblem on the PRO. Part of the problem is identifying exactly what it sounds like.
Hereis a message from the by Sean, K3XT, thatis a good description of how to hear the problem for yourself (or at least one version ofit) (reprinted with permission). I was on 40m this morning and ran across K8JW saying how he returned hisPro because of unacceptable DSP intermod problems in crowed bands.
Hesaid he contacted Icom and they refused to acknowledge the problem. Hetold me how to hear these intermod products.
I tried the belowprocedure and sure enough you can hear them. Note, this is intermodproducts not an audio distortion issue.-SSB-Select SSB filter of choice. Tune VFO to a quiet area of a band that hasS8 or stronger signals on either side (+- 10 KHz) of your VFO frequency.Set your band scope to +- 12.5Khz to see these signals transmitting.Put on your headphones (in my case Heil pro set that have a good bassresponse). Turn the audio (AF) knob full counter clockwise (off) thenturn it clockwise till you hear a faint pop (7:30 position)(DSP audiohas just kicked in).
You can hear a faint low tone rumble of the variousmixing products of the adjacent signals. You can see the signals onyour scope corresponding to the intermod you hear. These intermodproducts are very faint and is a non issue because as you turn thevolume to a normal audio level (9 o'clock) the noise and/or signalquickly masks these intermod products. The intermod products do not getlouder as you up the volume control.
It is a different story on CW.-CW-Select CW filter #2 (500Hz). Tune VFO to a quiet area of a band that hasS8 or stronger signals on either side (+- 10 KHz)(actually, one signalwill do) of your VFO frequency. Set your band scope to +- 12.5Khz to seethese signals transmitting.
Put on your headphones. Turn the audio(AF) knob and set your volume to a comfortable level, in my case it is 9o'clock. At this point you will hear what sounds like key clicks thatare very low in frequency. You will hear these intermod products evenat normal volume levels.
Even if you tune the VFO to a CW signal, youcan hear these low level intermod products between the pauses of the CWcharacters of the station you are listening to.I can not hear any of these intermod products with my SP-21 externalspeaker, only with my headphones. Serial number for my Pro is 1698.Sean - K3XTI can hear these artifacts on my PRO as well. I don't think that the word intermodtechnically applies because intermod or cross modulation requires two signals. Theseartifacts can be heard with a single signal. That's really not important, since the soundsare real. They are weak, but they are there.In my opinion, these sounds are part of the overall brittle soundthat I hear from the PRO. Normal SSB and CW signals are surrounded by little clicks andpops and thumps.
I believe that they are artifacts of the IF DSP stage. Again, a signatureof the technology at this point in its evolution. These sounds are not found on analogradios, at least the ones that I have used, including the 756. I also find that thesesounds do not interfere with copying the desired signal. They are a distraction at best.Since this page is about comparing the 756 to the PRO, I thought I wouldconduct a CW keying test. I set up my 756 to transmit into a dummy load on 28.100 MHz. Ituned the PRO to the same frequency.
By adjusting the transmit power level, and thereceiver attenuator, I was able to create signals at three levels, S9, S9+20 dB, and S9+50dB. I transmitted a string of dits and tuned the PRO above and below the center frequencynoting when the CW signal was no longer detectable in a pair of headphones.
I thenreversed the setup, and transmitted on the PRO, and received on the 756. Here's what Ifound. The detectable bandwidth is listed in the table. Both radios had a 350 Hz CW filtersetting. S9S9+20 dBS9+50 dB756± 2.25 KHz± 8 KHz± 25 KHz756PRO± 8.5 KHz± 10 KHz± 13 KHzFor very strong signals, the 756 is twice as wide as the PRO.
An averageS9 signal, however, can be heard ± 8.5 KHz on the PRO (only ± 2.25 KHzon the 756). The artifact that is heard is very weak. It does not affect the receivergain, and it does not obscure real signals.The IF DSP on the PRO makes it a new radio and new experience. For me, Ican live with the artifacts in order to get so many filter positions.
The artifact soundsare unexpected, but I do not find that they interfere with copying the desired signal,even when it is a weak CW DX signal with many callers only a few KHz away.Both radios feature adjustable bass and treble settings on the transmitaudio. The 756 allows adjustment from -12 dB to +12 dB in steps of 2 dB. The PRO settingsgo from -5 dB to +5 dB in steps of 1 dB. On the air testing suggests that PRO range isindeed limited, and does not provide significant changes.The PRO features three different transmit audio bandwidths (on SSB). Thebandwidths are fixed, and are called narrow (2.0 KHz), middle (2.6 KHz), and wide (2.9KHz). The width does indeed change, and is clearly detectable both by another station, andin the audio monitor.
Note that the transmit audio bandwidth is independent of the receiveaudio bandwidth.NOTE: In January of 2002, I learned that some amateurshad discovered that models of the 756 past a certain serial number were built with a normal/widetransmit audio bandwidth switch. The serial number of the change appears to be around3,000. The switch is totally undocumented, and is located within the radio. The switch,S801, is on the bottom of the radio. I do not know where it is located.
The swiched ismarked N (normal) and W (wide). By default, it should be in the N position. If you movethe switch to the other position, your transmit audio bandwidth will become wider.When the first rumors of the PRO broke, I was hoping that ICOM would addIF DSP to the 756, while keeping the existing 756 IFs and filter arrangement - perhapswith a few more filter slots. The PRO implements a different set of IFs, with theDSP at the last stage before conversion to audio. The DSP is responsible for almost all ofthe receiver selectivity.
In the end, DSP still does not seem completely up to the task,although it is getting very close.It's hard not to compare the 756 and the PRO against the Yaesu FT-1000MP,and the new Mark V. The Yaesu radios are known for their immunity against interferencefrom strong signals near the desired frequency. Still, the DSP implementation in the Yaesuradios, in my opinion, is very primitive. What I would really like to see is a quadconversion receiver with a Yaesu front end, complete with extensive filter options at 2 IFstages. The final IF stage would be the PRO implementation. For me, this would be anirresistible combination. The early IF stages would establish the approximate desiredbandwidth, and the final IF DSP would realize the exact desired bandwidth.update, June 2002: The TenTec Orion appears to take this approach,and is a blend of the strengths of the Yaesu and ICOM radios, whileattempting to fix all of the problems.
If it can perform up to expectations,it should be a very fine radio.The ICOM PRO II is an update of the PRO. It completely replaces the PRO,and ICOM has discontinued manufacturing of the PRO, building only the PRO IIinstead.
In my opinion, it a evolutionary update, not a revolutionary jump forward. Atthis point in time, the radio is starting to be used by amateurs. Detailed use informationis just becoming available.In visiting the excellent web site of, I discovered a link to an.
The manual may also be downloaded from the This web site contained an on-line copy of the PRO II user's manual, whichapparently was submitted to the FCC as part of the approval process. I downloaded themanual, and compared it, page by page, to my PRO manual. While I make no claims that Idiscovered every difference, those that I did find are listed in the following paragraphs.By early 2003, ICOM made available many of its manuals on.
Clickon Download.1. In general, the time that you have to hold in a button to activate analternate function has been reduced from 2 seconds to 1 second. This appears to applyacross the board.2. The front panel Bk-In Delay and Key Speed knobs have been swapped.3. The Speech button has been turned into the Rec/Play button for Audio RecorderChannel R4.4. The Lock button has been turned into the Lock/Speech button. To activate the'old' Speech function, press the button for 1 second.5.
Icom 756 Pro Iii Serial Numbers Lookup
The Screen Menu Arrangement is changed. When completely backed out of alllevels of menus, the 'soft' buttons are now labeled: Scope, Voice, Keyer, Memory, andScan, as opposed to Scope, Voice, Memory, Scan, and Set.6. New Noise Blanker level set mode.
Adjust the value from 0 to 100 percent.7. New DSP Filter Shape set mode. Select Soft or Sharp for CW and SSB.8. New Preamp explanation section.9.
DVR Explanation improved. 90 total seconds of XMIT audio capture possible.10. One-touch voice record and playback described.11. Reference to IC-PW1, IC-4KL, IC-2KL/IC-AT500 in the original PRO manualreplaced with just a reference to the IC-PW in the PRO2.12. Display Type. There are now 8 display types, as opposed to 4 in the PRO.13. DSP Filter Set Mode described.
Soft/Sharp selections.14. Quick Rit/ DTX Clear set mode described.15. SSB/CW Synchronous Tuning set mode described.
Claims to keep the signal tunedin, even when going from SSB to CW. The frequency may be automatically shifted.16.
CW Normal Side Mode added. Selects the carrier point of CW mode from LSB andUSB.17. External DVR (digital voice recorder) triggering interface schematicpresented. Uses pin 3 from the front panel microphone connector. By using up to 4switches, and some resistors, you can trigger any of the recorder channels, or the CWmemories (if in CW).18. CI-V radio address (default) is 64h on the PRO2 and 5Ch on the PRO.19. General frequency coverage now specified by country.
5 countries specified.CommentsI composed the following comments for the ICOM reflectorNo new controls or connectors were added to the case. I am talking aboutphysical holes.It has already been discovered and reported on this reflector that you can use - on CW, with theexisting PRO. As best as I can tell by experimentation, you cannot get at the CW or'shaper' filter in SSB. I do not know if the 'soft' and 'sharp' filter shapes in the PRO2are something new and different. If they are not, then there is no net improvement for CW,and the only change is that you can now listen to SSB with the 'sharp' CW filter shape.
Iwonder if that's useful?I felt that the PRO digital voice recorder was nearly useless due to the user interface.The PRO2 is much better, what with the dedicated front panel button, and the ability toconnect a simple external switch to trigger playback. That same switch works with the CWmemory keyer too, which is a definite enhancement.
Icom 756 Pro Iii Review
Still, you cannot trigger the recorderfrom the computer interface, which would make it possible to run the radio completely fromthe computer keyboard, which is often very nice in contest situations.For me, the possible added value of the PRO2 comes down to the receiver changes. Untilsomebody can do a side-by-side comparison, it's all guessing. My only fear is that ICOMmade changes that impact measurement numbers, but did not really improve the receiver.Many folks really follow the numbers in the various popular reviews, and take them as anabsolute ranking of the current crop of radios (usually to justify their purchasedecision). A few dB will change certain rankings, but might not be audible. I hope thatthe changes do make a (useful) difference.Anybody directly comparing the PRO2 to a PRO should also see if the new 'soft/sharp' CWfilter shapes are what already exists on the PRO. My guess is that they are the same,meaning that all that has been added is the ability to listen to SSB with the 'sharp'filter shape. It remains to be seen if that is a good thing.Last update:Wednesday, February 26, 2003 05:59:55 PM.