HFU HF Underground
Technical Topics => Equipment => Topic started by: Looking-Glass on July 26, 2018, 0723 UTC
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Finally, in the last few days I have had the opportunity to put the newly purchased Icom IC R-75 communications receiver through its paces and compare it with my long trusted Yaesu FT-2000D transceiver, which also doubles as a comms receiver. Some of the regulars asked me to post what I think of the radio so here I go:
I was fortunate enough to purchase one of the last two brand new IC R-75 receivers from Icom Australia down in Melbourne, I was told this line ceased production some two years ago.
Primarily, I purchased the radio for LW and MW DXing and it has not let me down and compares well to the Yaesu.
On MW I noticed that many stations are distorted and this was rectified by switching out the Noise Blanker, beautiful clear reception with the NB switched off. It pulled in ZB Talk Radio in Wellington, New Zealand (around 2,200kms distance) quite well on my evening Grey Line and compared well to the FT-2000D reception of same.
Early this morning the NDB band was performing well and the following were logged:
1534z FRT 278KHz Forrest WA for 2,191kms 319-419 report.
1536z LEO 377KHz Leonora WA for 2,793kms 319 report, new logging, first time heard.
1541z WLU 383KHz Wiluna WA for 2,973kms 419 report.
1548z KA 404KHz Karratha WA for 3,581kms 419 report.
1624z WP 377KHz Weipa QLD for 2,468kms 319-419 report, this beacon not heard for around two years.
1631z GV 380KHz Gove NT for 2,783kms 419-519 report.
1905z TNK 272KHz Tennant Creek NT for 2,224kms 519 report.
The above loggings attained by NOT using either Pre-Amp-1 or Pre-Amp-2, running 380 feet of wire via the PL-259 plug to the radio SO-239 socket. I found reception of weak NDB's much clearer without introducing the PreAmp functions. The PreAmp both 1 & 2 increase the noise threshold too much, so left off. I did introduce the Twin PBT function and found it clarified some of the weaker NDB's pulling them out of the noise but for the majority of the time this function was left off.
Unfortunately the band was not open to New Zealand but I did log Kaitaia, New Zealand on 238KHz 519 report around 1130z a couple of nights previous for 2,081km on the R-75, its first overseas logging.
Surprisingly the R-75 doesn't seem to attract as much crud and birdies from MW on the NDB band that the FT-2000D does and I didn't really need to use the home brew filter (cut off at 500KHz) that is in line all the time with the FT-2000D.
The digital bar graph signal meter seems to lack with NDB local beacons, about a one and a half to two 'S' points difference compared to the analogue FT-2000D meter.
The small speaker at the face of the radio is a little bit of a let down, but once you get used to it things are fine, however, I find by connecting it to the Yaesu SP-8 external speaker (matches the old FT-1000D transceiver) with High/Low filters the R-75 sounds a lot better also NDB reception audio is enhanced by tweaking the High/Low filter switches on the SP-8 speaker.
Receiver noise level is excessively high until you connect an earth wire to ground, so using the R-75 in the bedroom is out of the question at present, thinking of filling a five gallon drum with good garden soil and run the wire to that and see what happens?
A surprise bonus was to find out that I have in fact the Asian domestic version of the R-75 with continual coverage from 30KHz to 60MHz, the Australian import version does not have this feature and cuts out at 30MHz and comes back in just below 50MHz I am told. So will be utilised well for the summer 50MHz DX season to check on rising MUF and out-of-band indicators.
Have filled up just over half of the 100 Memory Channels with NDB and M89/V07/HM1 frequencies plus some aviation and marine frequencies.
On the Tropical Band section of SW it pulled in the regular stations I hear from the USA, Pacific and Asia on the FT-2000D with ease and nice audio (providing the NB is left off). The test will come this weekend when I chase African shortwave DX between 3 and 7MHz in my early mornings.
Not into digital bar graph style signal meters but beggars cannot be choosers I guess, signal strengths compared with the analogue meter on the FT-2000D are favourable and acceptable.
Bit disappointed that no internal AC power supply, as with the majority of HF comms receivers of days gone by. Not real keen on the AC adapter method of providing power, time will tell. Another irritation is the poor quality Earth connection via a plastic push mount next to Antenna-2 long wire connector. Should have been a more solid wing nut connector towards the bottom of the radio.
In built speaker is suffice, but could have been better, once you get used to it it's acceptable, external "quality" speaker is the way to go.
Be interesting to see what advantages the optional UT-106 DSP Unit and Automatic Notch Filter features have to offer, perhaps someone reading this has these two options and can comment on their worthiness?
Also it will be most interesting to see how it performs in the 30-50MHz sector when the six metre band summer DX season rolls around as I am a very keen 50MHz DXer with 75 DXCC countries confirmed.
Overall, I am happy with the radio and look forward to many hours of DXing with it... ;)
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Good to hear you are happy with your new R75. ;)
A real analog S-meter beats the bar graph any day.
A comfortable headphones is my choice for weak signal listening. IMHO, the small speakers on most radios are inadequate.
All my stuff runs off a 12 volt battery... no power supply noise.
Enjoy your new radio. :)
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A friend of mine sold his IC-R75 recently, and it beats me why he did that, since I don't know what he replaced it with. He got rid of a TS-870 also. (That was a beautiful rig in every respect as well.) Anyway, In the long run, you'll get lots of enjoyment from this rig. I don't think that the "S" meter is bad in the R75, albeit I'll take that nice 'ol Icom classic analog meter in my IC-745 anytime over any digital bargraph meter. As far as having to power with an external power supply? In the long run, that is actually a better option. Why's that? It's been my experience that internal power supplies generate more than 1/2 the heat in a rig and age the components faster and cause FREQ drift. I experienced that 1st hand with a TS-711A 2M all-mode rig, (Cousin to the famed TS-440 HF rig.). I ran it for years with the internal Kenwood PS in it and it did indeed add to 5/8th more heat to the rig, even on idle receive. Then I read in the 1990's that one of Kenwood owner's biggest gripes were the failure of the Kenwood internal power supplies, and the heat that they pumped into the rigs that they powered. Long story short, I later ran my TS-711A with an EXT PS, and it indeed ran much cooler, but the damage was done, and today that rig is still wayyyyyyyyyyyyyy off FREQ on me. Come to think of it, I ran the internal PS in an old Kenwood R1000, and that 1st 30min, it would drift almost 1kHz, then stabilized. Bet ya that if I ran that with EXT PS the drift would have been less. (Damn, I miss that fun rig.) The point is, an EXT PS, especially if it's a linear power supply, and not switching, could help make that rig last almost twice as long and let you enjoy RX'ing with less noise. Annnnnnnnnnnnnnd, your idea of a GND line to a large-ass bucket of soil? Even better. Try a bucket of brine, i.e. salt water. Way more conductive than soil. Finally, try that R75 on DX'ing MW stations as well. It won't be the best sounding receiver for that, but you'll get some nice catches for sure. As far as audio quality goes on it? Got a bookshelf stereo speaker that you can add to it? And, I understand that there is a MOD to open up the audio in the R75, so that you can appreciate the audio from some of those catches. For that, and other neat MOD's, I believe that there's a Yahoo Group for that to join up.
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I assume there's a way to adjust the levl of the nb? What i do is find a strong but unsteady sig and tune off a kc or so and then adjust the nb for the highest it can go without causing the signal to distort. Then you should be pretty good to go with respect to any strong sigs. You don't want a steady strong sig to adjust with as that sets the agc and keeps it at a specific level, a strong voice ssb sig is pretty much ideal for this.
On the dsp option, I find it excellent for notching, and set to about 4 in noise reduction when noise reduction is desired worked well for me. In the end, the dsp option is worth it for the autonotch alone.
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Pinto Vortando: Thanks for your feedback, yes, cannot agree more about headphones, had a good set of Marconi Marine headphones from my times at sea in the late 1970's but they were lost in between moves about 30 years ago. Had a pair of Kenwood headphones but too "heavy" on my ears so don't use them, they fell to pieces after 10 years. Good on the 12 volt battery, bit cumbersome here, by the way, what hours do you get off one full charge of the battery?
ThaDood: Interesting comments and observations, all taken in. As for the brine in the earth bucket, well I live around 250kms from the ocean in the mountain area west of Sydney so no brine for me. Good heavy earth kept damp will be probably the way to go and see what happens. I often question the accuracy of the bar graph strength meter from time to time. Just too used to my two big Yaesu analogue meters on them I guess.
Josh: Not greatly worried about the Noise Blanker, it's just a push button function on the R-75 unlike the FT-2000D which is adjustable, thanks for your the comment on the DSP option, will ring Icom and see if they are still continued and in stock.
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Pinto Vortando: Thanks for your feedback, yes, cannot agree more about headphones, had a good set of Marconi Marine headphones from my times at sea in the late 1970's but they were lost in between moves about 30 years ago. Had a pair of Kenwood headphones but too "heavy" on my ears so don't use them, they fell to pieces after 10 years. Good on the 12 volt battery, bit cumbersome here, by the way, what hours do you get off one full charge of the battery?
ThaDood: Interesting comments and observations, all taken in. As for the brine in the earth bucket, well I live around 250kms from the ocean in the mountain area west of Sydney so no brine for me. Good heavy earth kept damp will be probably the way to go and see what happens. I often question the accuracy of the bar graph strength meter from time to time. Just too used to my two big Yaesu analogue meters on them I guess.
Josh: Not greatly worried about the Noise Blanker, it's just a push button function on the R-75 unlike the FT-2000D which is adjustable, thanks for your the comment on the DSP option, will ring Icom and see if they are still continued and in stock.
You can make your own brine by pouring water over some rock salt in the bottom of the bucket and stirring it well. A lot of CB'er's still use the "brine bucket ground" if their shack is on the second floor as the ground wire from transceiver to the ground outdoors can be resonant in the CB band.
I remember versions of them going back to when I was a kid, and that was a long time ago. Use a plastic bucket if you go that route, the tales of galvanized buckets and washtubs being corroded by the brine were and are legendary.
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Pinto Vortando: Good on the 12 volt battery, bit cumbersome here, by the way, what hours do you get off one full charge of the battery?
Actually have a couple of 12 volt batteries here in the shack under the bench. They get charged once or twice a week depending on usage for several hours with my small 1 amp charger.
Once a month they get an equalizing charge with the big charger. The smaller battery of the two is a garden tractor battery that gets replaced every year or two in the springtime when the tractor batteries go on sale and can be had for less than 20 bucks. The larger battery is from my car. My car batteries get replaced every 3 years. The car battery goes into the shack and the shack battery gets turned in at the auto parts store. The key thing is to not let the batteries get discharged too far. Deep discharge and not recharging promptly is a good way to quickly kill a SLI type battery.
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Sorry... I'm somewhat skeptical of a bucket of dirt in the shack being even remotely useful as a electrical ground. Maybe you can grow a tomato in it, with enough light? ;D
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Sorry... I'm somewhat skeptical of a bucket of dirt in the shack being even remotely useful as a electrical ground. Maybe you can grow a tomato in it, with enough light? ;D
I was thinking the same thing. To me it sounds more like a short makeshift counterpoise which may help a bit but is no way a RF ground or earth if you prefer.
cheers, G near ottawa Canada
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I was thinking the same thing. To me it sounds more like a short makeshift counterpoise which may help a bit but is no way a RF ground or earth if you prefer.
Yes, this OTOH seems entirely possible. I seem to recall MFJ had a device to do this with a random wire (MFJ makes a lot of devices to do things with random pieces of wire). IIRC I have also seen plans to make your own, often using a tuned LC circuit, and a meter or even light bulb as an indicator for a proper adjustment (assuming you're using this with a transmitter).
Speaking of proper grounding (or rather, changing the topic to proper grounding, from improper grounding), I have been on a grounding kick here. My two new recently installed beverages (south and west-southwest) have a run of about 175 ft of coax or so. This run along a fence line most of the way, about a foot above ground. Then underground and above ground another distance to a post where each antenna starts. The coax runs are not one length of coax, but made of several shorter lengths. Yesterday I decided to add grounding rods and connections to each location where two pieces of coax connect. Too soon to observe any obvious improvements, but it makes me feel better.
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Sorry... I'm somewhat skeptical of a bucket of dirt in the shack being even remotely useful as a electrical ground. Maybe you can grow a tomato in it, with enough light? ;D
Agreed, I am thinking the exact same thing. Just run a wire out the window to the ground, or ground it to the ground of the ac outlet. So what if the ground wire's a wavelength on 10m, it'll work better and better the lower you go freqwise. I had a 3/4wl 10m antenna up about 1wl, with the ground rod directly below antenna, not only did it work great on 10m it was freaking amazing on vlf. This is reminiscent of a study done by USN on hf rx antenna traits, they determined that a 6ft vertical over a good ground plane (ie a ship) matched to the line was just about all one needed in many cases.
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I've got a second floor shack, the outdoor spigot is about 12 ft. directly below the window, so I've never had to sweat grounding my radios upstairs or the skyhooks before they go in the house.
When I was still pirating, the studio was in the shack. I didn't want to use the outdoor ground as the wire picked up all sorts of radio traffic from the nearby police and fire station. I got a 500 ft. spool of 16 gauge wire at hamfest for five bucks for that stuff & ran a short length of it to the audio equipment. I broke a couple of toes on it, but it worked.
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Going to look at the five gallon plastic drum of earth and salts kept damp as a first option to see what happens.
Josh: Only concrete out side of my bedroom window and a copper water pipe running along the external wall, may try that if the indoor bucket of earth/salt fails... ;)
Little IC R-75 given a run on 2-6MHz last night and was impressed with its results monitoring mixed bag of aviation on USB, M89 on CW and general low band shortwave on AM.
M89 logged on 3.378MHz CW at 1411z running the C4TY/NSF5 round slip around a 419 report impressed me as is was not much better on the big FT-2000D in comparison. ;D
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If the copper pipe's a cold water pipe (ie not directly connected to the water heater) and not a gas pipe you will likely find no better ground.
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Josh: Yes, its copper cold water pipe, will find some heavy wire and run the earth to that and see what happens, last resort.
Interesting, yesterday between 1330 and 1420hrs local we had an electricity black out, there was zero noise right across the HF spectrum as a result.
Tuned right across HF with the battery powered Tecsun-2000 and amazed how clear and noise free, just goes to show the HF interference is being generated by the electricity supply lines out front of the house.
Other than the earthing issue, very pleased with the little Icom IC R-75 so far... ;D
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Sorry... I'm somewhat skeptical of a bucket of dirt in the shack being even remotely useful as a electrical ground. Maybe you can grow a tomato in it, with enough light? ;D
Chis, I overwinter serrano peppers that I grow in pots in the backyard indoors under a couple 23 watt CFL's for each. They fruit year round.
Looking-Glass, I used to do some dx'ing at an old family farm you had to hike a good mile plus into to get to the house. The power line to that place went down in a storm in the 80's. There is nothing around it but abandoned farms. The first time I took a portable in that could handle a sizable antenna I was so shocked at the lack of noise I began to wonder if I hadn't damaged the radio on the way in? I tuned to the 40 meter band and found the DX booming in. I was absolutely stunned.
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Pig Meat: Just goes to prove the "filthy energy" they pump out for domestic use eh?
Yes, I couldn't believe how noise free the band was while the juice was off while I was on the battery powered Tecsun-2000.
Didn't have this problem when I was living in Sydney as the residential power supply was all under ground. Reduced the noise further by running a bit of extra lead through the window to the copper water pipe on the wall outside, can hear most of the local NDB's now and quite a number of MW stations not previously noted.
Noticed on Saturday the lethal amount of RF generated through HF from the Fisher & Paykel washing machine too, not to mention the crap from the new Samsung "Digital Technology" refridgerator.
Earth bucket will be ideal for those tomatoes now...maybe Truss would be nice eh? ;D
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This is reminiscent of a study done by USN on hf rx antenna traits, they determined that a 6ft vertical over a good ground plane (ie a ship) matched to the line was just about all one needed in many cases.
Josh,
Do you recall the name of the study or the source for this ?
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This is reminiscent of a study done by USN on hf rx antenna traits, they determined that a 6ft vertical over a good ground plane (ie a ship) matched to the line was just about all one needed in many cases.
Josh,
Do you recall the name of the study or the source for this ?
Wish I did, I fear it was in one of the myriad 1950s thru 60s qst issues I bought by the box from Ladd Electronics at 41st and Dodge in Omaha during the 90s. I miss that place and the cheap reading! Frank was a great guy. More on topic, it was just a statement that was profound enough for me to memorise it, and it seems to be fairly accurate.
I had that 11m whip up about a wl and it did fantastic from vlf to hf, never tried it above hf. I used a Grove minituner with it for vlf and hf outside 11m. The vlf performance was what amazed me most, but have to mention that part of Nebraska (Omaha) is atop some of the most conduictive soil on the North American continent, so that surely plays a part.
As my hfdf effort gets rolling, I anticipate using some 1/4w cb verticals as the df antennas and will let on how goes it with cb antennas on vlf/hf.
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Yes, I couldn't believe how noise free the band was while the juice was off while I was on the battery powered Tecsun-2000.
Noticed on Saturday the lethal amount of RF generated through HF from the Fisher & Paykel washing machine too, not to mention the crap from the new Samsung "Digital Technology" refridgerator.
Just when you think you have solved the noise issues, a new piece of digital garbage shows up …
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This is reminiscent of a study done by USN on hf rx antenna traits, they determined that a 6ft vertical over a good ground plane (ie a ship) matched to the line was just about all one needed in many cases.
Josh,
Do you recall the name of the study or the source for this ?
Wish I did, I fear it was in one of the myriad 1950s thru 60s qst issues I bought by the box from Ladd Electronics at 41st and Dodge in Omaha during the 90s. I miss that place and the cheap reading! Frank was a great guy. More on topic, it was just a statement that was profound enough for me to memorise it, and it seems to be fairly accurate.
Got an ApexRadio vertical here, works amazingly well for basically a 6' piece of wire.
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I saw an article in a late 90's QST of a vertical with a capacitive hat mounted on mast in an approx. 10 yd. in circumference, 3 ft. deep tank of salt water by the gang from Newington. It may have been 15 ft. tall if that much. They designed for both transmitting and receiving and the published results showed excellent performance up and down the bands.
I've often wondered if you couldn't do the same with a kiddy pool for listening?
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My friend who has the wall of JRC gear swore by slopers and HAM hf band verticals for swl. He used some kind of ground enhancing chemical that didn't kill the grass, and watered it every few days. Being at the time just south of downtown Omaha, he had a gigantic noise floor and fought for every scrap of signal he could get.
On the nutcases from Newington, if they'd replaced that tank of salt water with a similar sized sheet of copper or a pipe I bet they'd have gotten the same sig strength readings. I can see my friends case working irl but not Newingtons.
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So far I am very happy with the Icom IC-R75 comms receiver, has nice audio when connected to the Yaesu SP-5 external speaker with filters, especially on MW and SW on AM mode. Does seem to be a fraction weaker on NDB band though, something 319 report on Icom is around 419 on the FT-2000D to the human ear.
Prefer the Yaesu on CW mode reception though, for some reason, maybe used to the Yaesu more?
Seems to be around an 'S' point to and 'S' point and half down on signal strength with local NDB beacons on LW compared to the FT-2000D, but then again there are a few thousand dollars difference in price between the two radio's. Could be meter calibration too, Yaesu FT-2000D has analogue meter compared to bar graph on IC R-75.
It always happens, when I bought the IC R-75 a friend in Victoria offered me his Yaesu FT-1000MP secondhand for $650.00, he has had it since new and has books and box etc, tells me it has a cracking receiver on the NDB band too...oh well, thems the breaks I guess. Could buy it as a spare set? ;)
Thanks everyone for your hints, tips, pros and cons concerning the R-75, all appreciated and taken on board...now to get rid of that pain of power line noise, that's another story... ::)
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Josh, I used to love slopers when I was pirating along with the upright "L", a variation on the dipole w/ similar characteristics. 5 minutes up and down, perfect for mobile pirating, and great for listening as they don't pick up nearly as much noise as a standard vertical but they have enough of it's characteristics to pick up low angle signals well before other antennas.
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Wich brings up another point related to USN antenna studies, slopers, and so on. Most people I know who use the t2fd used it as a horizontal antenna and they say it sucks. Apparently one needs to slope the t2fd to get the best performance out of it. The t2fd was created at the Naval Research Laboratory far as I know, becoming a fav at shore stations and NSA both.
I'd definitely unload the r75 and get the ft1000 if had the chance. I didn't like the wooly audio of the 1000 I played with for a few minutes, but there are few rigs that can compare to its signal handling abilities and filtering.
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Slopers work very well, my 43 meter folded dipole is mounted that way.
I had a T2FD for many years, it was about 130 ft long, and mounted sloped, which as Josh pointed out is what you want for best performance. Due to the length, it was probably not as sloped as was ideal, but it was still a good performer, especially on the lower bands. As with other loop style antennas (that is, a continuous piece of wire, I'm including folded dipoles in here as well) they often have lower noise than dipoles.
My 20 and 10 meter dipoles are not folded, but noise is often less of an issue (for me anyway) on the higher bands.