Is the receiver's circuitry in the Icom IC-718 transceiver the same or at least very similar to Icom's IC-R75 receiver?
Icom: IC-718 Transceiver/IC-R75 Receiver circuitry?
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You looking to buy one of them? I would get the Icom 718 just in case you ever decide to be a ham.
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While they are very similar, and use similar technologies, they are not the same. Coming out of the same design house that is pretty understandable, engineers are creatures of habit if the technology applies. I have often heard things along the lines of "the 718 is an R75 with a transmitter added", this is simply not the case.
At the most basic levels the R75 is a triple conversion radio, while the 718 is double conversion, and the R75 tunes a wider frequency range. That alone will tell you there are some differences between them, the triple vs double is significant. However they do use very similar IFs (not uncommon across a specific manufacturer), similar BPFs, etc. The layout of the boards is completely different, there is essentially no resemblance there until you get down to the layout of some of the circuits on each board.
T!
At the most basic levels the R75 is a triple conversion radio, while the 718 is double conversion, and the R75 tunes a wider frequency range. That alone will tell you there are some differences between them, the triple vs double is significant. However they do use very similar IFs (not uncommon across a specific manufacturer), similar BPFs, etc. The layout of the boards is completely different, there is essentially no resemblance there until you get down to the layout of some of the circuits on each board.
T!
I've had both for about 10 years in the past. The R75 has the better receiver - that is a much finer level of control compared to the 718.
Operationally, the 718 has an agc that is faster than the R75's slow setting. So fast, that it was annoying enough to me to modify the radio to use the slower AM agc circuitry.
The 718 has a hot front end. Really designed for the mobile back at the turn of the century with your usual hamstick.
So hot that many low-band users manually went inside and turned down the internal gain. I didn't need to since I didn't have anything like a full-size dipole or inverted vee up for the lowbands. Preamp - again, too much gain unless the band was absolutely, and I mean absolutely quiet. Mostly irritating more than helpful. Icom went over the top on that.
The R75 had much finer control, and the agc speed while quick on slow speed, was tolerable I guess but it always bugged me to make the AM agc speed mod for ssb....
Operationally, the 718 has an agc that is faster than the R75's slow setting. So fast, that it was annoying enough to me to modify the radio to use the slower AM agc circuitry.
The 718 has a hot front end. Really designed for the mobile back at the turn of the century with your usual hamstick.
So hot that many low-band users manually went inside and turned down the internal gain. I didn't need to since I didn't have anything like a full-size dipole or inverted vee up for the lowbands. Preamp - again, too much gain unless the band was absolutely, and I mean absolutely quiet. Mostly irritating more than helpful. Icom went over the top on that.The R75 had much finer control, and the agc speed while quick on slow speed, was tolerable I guess but it always bugged me to make the AM agc speed mod for ssb....
I wonder why Icom stopped manufacturing the IC-R75 and never introduced a replacement?
Possibly because they released the IC-R8600 and the market for communications receivers is small.
Also, if the IC-R75 and IC-718 use some of the same parts and those parts are in short supply, Icom may have decided to concentrate the remaining parts on the IC-718 which still seems to be a good seller for them.
Also, if the IC-R75 and IC-718 use some of the same parts and those parts are in short supply, Icom may have decided to concentrate the remaining parts on the IC-718 which still seems to be a good seller for them.
The price of the two rigs was pretty close when they came out if I remeber right it was within like $75 of each other,so you could buy the reciever or pay a tiny bit more and get a 100 watt trasmitter thrown in .they have built many more 718 after they discontued the R75 .you can still find new 718's for sale but youll never come close to finding accesories like mounting brackets R75,718,910AH all use them ,and cant be had anywhere for any price i bought them new 8 years ago ,and been looking ever since....
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My guess for the R75 going away? The desktop receiver market virtually went away as many international shortwave broadcasters closed down their 100 and 500 kw transmitters and moved broadcast operations to the internet and/or local FM outlets fed by satellites. To be sure, some transmitters and services (mostly in the tropical bands) remain but the selection is a mere shadow of what it was in the 1950s through the 1990s. Look at the older World Radio TV Handbooks and compare them with the current editions.
Utility listening--aero, marine, PTP (what little remains)--had a smaller listener population back when. This segment of the listening hobby has also faded into the noise level.
FWIW, I started listening to SWBC in 1952. My first receiver was a 1943 Hallicrafters S--38; my last desktop receivers were the JRC NRD-525 and -535. Over the years, among the many receivers on the desktop, I had an R75... my review of the unit is on the web at Medium Wave Circle - Receiver Review: ICOM IC-R75 (originally published on the Radio Netherlands website February 28, 2000).
Utility listening--aero, marine, PTP (what little remains)--had a smaller listener population back when. This segment of the listening hobby has also faded into the noise level.
FWIW, I started listening to SWBC in 1952. My first receiver was a 1943 Hallicrafters S--38; my last desktop receivers were the JRC NRD-525 and -535. Over the years, among the many receivers on the desktop, I had an R75... my review of the unit is on the web at Medium Wave Circle - Receiver Review: ICOM IC-R75 (originally published on the Radio Netherlands website February 28, 2000).
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