RETRO RECEIVER REVIEW #24 - The RACAL RA-1771
RETRO RECEIVER REVIEW #24
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Racal RA-1771
by Craig Seager VK2HBT
This review first appeared in the Australian DX News in May 2009. Once again, I extend my thanks to Craig Seager for contributing this retro review to MEDXR and helping to keep the memories of radio alive!
All images in this article can be clicked on for an enlarged view and closer inspection.
For this outing, we seek to correct an imbalance by revisiting an iconic British brand name in radio terms that deserves more emphasis within this series. Hmmm… what do we have on the shelf that might help us out in this regard? Ah, yes, here’s something!
UK-based Racal Limited is synonymous with quality electronic equipment, and the company (founded in 1950 by RAymond Brown and George CALder Cunningham) was responsible for some legendary communications receivers, mostly supplied under government contracts.
The RA-17 was one such: based on the Wadley Loop principle and built like a tank. Thousands of these made their way into military and maritime applications, and subsequently into the hands of hobbyists via the surplus market. Accurate to 1 kHz utilising an analogue sliding tape display, and very sensitive, the RA17 and other variants were arguably a match for the Collins equipment from the other side of the Atlantic that impressed so many commentators.
There are several resources on the internet that give good overviews of the RA-17, such as here:
https://www.radiomuseum.co.uk/racal.html
and here:
https://www.tdxc.net/wp-content/uploads/2023/07/pr19-THE-RACAL-RA-17-COMMUNICATIONS-RECEIVER.pdf
Despite the success of these post-war valve receivers, the move to solid-state technology in the 1960s brought just as much pain for Racal’s customers as it did to those of other manufacturers. The early semiconductors certainly had their limitations, and even high-end receivers such as the RA1218 and RA6217 (1968) were misfires, with all sorts of birdies, whistles and images in evidence. By the late 1970s, however, componentry had improved to the extent that some nice, solid-state units were making their way onto the amateur market, and even better sets could be bought by government and commercial-sector bodies with the requisite deep pockets.
The RA-1771 was one of these, released in 1978, and boasting modular construction with up to 9 separate PCBs, depending on options fitted.
There are radios that shout their pedigree from across the shack, big and bold and festooned with knobs. The Racal RA-1771 is not one of these! In line with much British radio engineering, it is understated and quietly competent. It is also a significantly weighty piece of technology and, once placed in situ, is best left undisturbed.
Somewhat uniquely for the marque, the RA-1771 is tuned by a 30-position MHz knob, plus five rotary decadic switches for kHz and Hz (the receiver can be tuned down to 10 Hz increments). Decade tuning was a briefly employed methodology for receivers primarily intended to sit for long periods on fixed frequencies, and is not handy for scanning across the bands. Other examples from the era that spring readily to mind are the Rockwell/Collins HF-8050, which had thumbwheels, and the Harris RF-550 with digital display and six vertical slide switches. Both are rarities in this country (though many years back I could have owned an example of the latter, which had been on an oil rig, if a lazy AUD $600 had been available for such purposes at the time)!
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| Decade tuning was a “thing” for a certain period of radio history. |
The RA-1771 is a fully synthesized PLL design, tuning from 15 kHz to 30 MHz in 30 bands, a departure from the Wadley Loop technology that had informed the RA-17, RA-117 and RA-1217 before it.
Modes available are AM, LSB, USB, CW, ISB and FSK. The frequency display is analogue, but precise. The circuitry is very similar to its sibling, the RA-1772, which was released around the same time but has a digital readout.
Up to five I.F. bandwidth filters can be selected, and these are well-chosen at 0.3, 1, 3, 8 and 13 kHz (when fully optioned). The standard receiver has a wideband input, but an optional tuned RF board can be added, with front panel control. This is a very stable device, by virtue of a temperature-controlled crystal oscillator (TXCO), and rated to 1.5ppm, though there are other, more stringent options available.
The top of the front panel is dominated by the tuning mechanism previously referred to, but there is also a small speaker that can be switched in or out, and a meter that has no less than ten measurement functions. Not only can it indicate RF, FSK and AF to line levels, but it also monitors the 20, 12, 5 and -7V supply rails. There are three AGC options (off/short/long), and rotary controls for IF gain, AF gain and BFO. Recessed screws adjust line output levels for AM/USB and LSB.
The rear of the set is rather busy, too. There is a BNC socket for antenna input, which is fused, plus various outputs for local oscillator, 1 MHz frequency standard, AGC, FSK, 1.4 MHz IF, external speaker and line.
Here too one will find voltage selection and a trio of power transistors and other I/O via tag connectors.
Performance across all bands is superior, with Racal getting it right on their first attempt at a fully synthesized set. Strong signals are handled well, and stability is excellent (high-quality FETs are employed through the signal path). There is also more than adequate protection for use in high RF environments (up to 30V continuous emf), according to the manual. This is achieved through a series of relays in the RF module, plus the antenna fuse.
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| A bank of electrolytics at the rear of the set. As with all vintage equipment, “when in doubt, whip them out! |
By using a bank of switched bandpass filters in the front-end, the radio exhibits relatively quiet characteristics.
It is likely that this set found its home in coastal stations, HF monitoring sites or even defence applications.
Usually, good money is needed to acquire a collectible such as this, so imagine my disappointment when the sensitivity of the example I acquired (many years ago now) appeared to be significantly sub-optimal. After a bit of obligatory “blue” language, some analysis was eventually done; a previous owner had bypassed the RF section completely, diverting the antenna directly into the mixer section. Reason: the active and earth sides of the RF output had been reversed by an unskilled tinkerer! Additionally, an additional protection relay had also been added, which is superfluous for operation in my part of the world. I suspect this was not working properly. Speculation suggests that this radio had previously been used in a more tropical location, where storms would have rendered it more susceptible to damage. So all was well in the end.
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| Modular construction helps with servicing, but don’t be fooled into thinking it will be a walk in the park. The components tend to be tightly packed. |
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| Module layout |
Fully optioned, the RA-1771 is certainly one of the best receivers produced in the late 70s/early 80s, but stocks on the second-hand market are low. Serviceability is rather good due to the modular construction and easily removable top plate. Sometimes the little tuning knobs can become de-glued from their display dials; a bit of a nightmare to get the numbers back in alignment with actual frequency should this occur to more than one at a time.
This receiver has been overshadowed by the classic RA-17 and impressive RA-1792. However, if “dull but worthy” meets your criteria, then it certainly hits that mark.
Accordingly, if you see one of these at a swap meet or flea radio market, set some notes free from your wallet without hesitation!
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| TCXO board, which provides a high-stability frequency reference |
Key Specifications:
| Specification | Details |
|---|---|
| Coverage | 15–30000 kHz |
| Sensitivity | <0.35 µV (0.5–30 MHz) |
| Selectivity | 8 / 3 / 0.6 kHz @ -3 dB |
| Tuning | Fully synthesised in 10 Hz steps, five rotary decadic switches for kHz and Hz selection |
| IF Rejection | >80 dB |
| Antenna Input | 50–75 ohm nominal, coaxial BNC connector |
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| RA-1771 signal path |
Resources:
The Operator’s Manual for the 1771/1772 can be found here:
https://blackradios.terryo.org/documents/manufacturers/Racal/manuals/Racal-RA1771-2-3-4-manual.pdf
The Maintenance Manual (Part 1) is here:
https://www.blunham.com/Radar/SignalsMuseum/PDFs/Recievers/RA1771_1.pdf
Part 2 here:
https://www.blunham.com/Radar/SignalsMuseum/PDFs/Recievers/RA1771_2.pdf
Missed the other Retro Reviews? Check them all out by clicking below:
Retro Receiver Review # 1 - The DANSK RX4000
Retro Receiver Review # 2 - The HITACHI KH-3800W
Retro Receiver Review # 3 - The SCHAUB LORENZ ITT TOURING T104A RECEIVER
Retro Receiver Review # 4 - The RACAL RA6790/GM
Retro Receiver Review # 5 - The REALISTIC (RADIO SHACK) DX160
Retro Receiver Review # 6 - The KENWOOD QR 666
Retro Receiver Review # 7 - The RODHE & SCHWARZ EK890
Retro Receiver Review # 8 - The YAESU FR101S
Retro Receiver Review # 9 - The SELENA VEGA B206
Retro Receiver Review # 10 - The DRAKE SPR-4
Retro Receiver Review # 11 - The NATIONAL RF-5000
Retro Receiver Review # 12 - The YAESU FRG-100
Retro Receiver Review # 13 - The MARC NR-82 F1
Retro Receiver Review # 14 - The MURPHY B40
Retro Receiver Review # 15 - The STROMBERG CARLSON AWP-8
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© Rob Wagner, Mount Evelyn DX Report, and contributors 2012-2026
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