RETRO RECEIVER REVIEW #18 - The PANASONIC RF-4800/4900 (DR-48/49)

RETRO RECEIVER REVIEW #18

My recently acquired DR-48. But it doesn't have the front-facing handles,
which appear to have been removed sometime in the past. Why would someone do that?

PANASONIC RF-4800/4900 (DR-48/49)

by ROB WAGNER VK3BVW



Perhaps you may have heard of the phrase "buyer's remorse" - the sense of regret or anxiety after having made a purchase. Well, I have "seller's remorse"! I regret having sold some of my previously owned and much-loved radio gear. My Panasonic DR-49 (a.k.a RF-4900) receiver is one such case. Owned somewhere between 1980 and 1995, this rig was foolishly sold to buy more ham gear. However, while owning this lovely radio, it was heavily used for some of my best DX catches and subsequent QSL verifications.

Then, in May 2022, a DR-48 (a.k.a. RF-4800) fell into my lap from a deceased estate. It is in very good physical condition, works well, and using it has brought back lots of memories. The '48 and '49 are very similar receivers. So this Retro Receiver Review will draw the spotlight on both rigs. But first, in order to help clear up some confusion, let's consider a little relevant history here.

Named after its founder, Konosuke Matsushita, and formed in 1917, the Matsushita Electric Industrial Co., Ltd. is one of the oldest electronics companies in the world. Starting out as a light bulb manufacturer, the company has had many transformations and developed a vast array of products in more than a century of operations. In 1927, the company adopted the "National" brand name. In later years, when exporting products to the U.S.A., the National moniker could not be used for trademark reasons. So in 1955, the company began marketing its U.S. export products as "PanaSonic" - a name created by combining "pan" meaning "all" with "sonic" meaning "sound."


The company continued to use the "National" brand within Japan where the name had become well-established. But, the "National Panasonic" brand was used worldwide, with the exception of in the USA where it was simply known as "Panasonic". Eventually, the Matsushita company dropped the "National" part of the name for Europe (1980), Australia and New Zealand (1988), and much of Asia (2004), running with just "Panasonic". But it was not until 2008 that the "National" brand name in the home country of Japan was eventually dropped and now markets itself simply under "Panasonic".

Why does all this matter? Well, depending on where you lived, the RF-4800 (a.k.a. DR-48) and RF-4900 (a.k.a DR-49) were produced under either "National Proceed", "Panasonic" or "National Panasonic" brand names. As mentioned earlier, the two rigs are very similar beasts. The RF-4800/DR-48 was released in 1976-1978, while the RF-4900/DR-49 appeared in 1979-1983.

There are several versions of these receivers on the used market: Proceed RJX-4800D (Japan), RF-4800 LBS or DR-48 in Europe, RF-4800 LBE in the United Kingdom, RF-4800 in the USA and DR-48 in Australia. Just change the "8" to a "9" for the next model in the series! In the DR-49, there was a second ferrite rod on the back of the rig for the European longwave band, with was not present on other models.

Around this time in radio equipment history, the push was to make smaller receivers. But the DR-48/49 seems to buck that trend. They have an imposing air about them in their black cases with front-facing handles. Considering they are solid state receivers, these bad boys are physically large, measuring 482 x 200 x 354mm (19 x 7.87 x 14 inches) and weighing in at around 8 kg (around 18 lbs). We certainly wouldn't class them in the "boat anchor" category, but they take up almost as much space on the table! 


In those days, for a short time, Japanese receivers often featured both digital frequency counters and the old-fashioned analogue dial cord moving pointer. In fact, in the DR-48/49, as well as the digital readout (accuracy to 1 kHz), there are two analogue cord dials: one for shortwave bands 2 to 8 (on the right), and the other for shortwave 1, medium wave and FM (on the left next to the front-mounted speaker). The big dial knob in the centre (SW 2-8) is a lovely two-speed design - push it in for fast tune across the bands, and pull it out for fine-tuning. To the left of the big knob is a smaller SW1/MW/FM tuning knob. Managing all these dial and band options are two band selector switches: the right-hand one for FM, MW, SW1, and SW2-8, while the left-hand switch changes bands between SW2 through to 8.

Oh, and by the way, the digital readout on the RF-4800/DR-48 is in red, and the readout on the RF-4900/DFR-49 is a soft blue colour.





There are plenty of other facilities on the front panel including:
  • Jacks for headphones/external speaker (4-8 ohms), recording output, and auxiliary input to connect some other audio source,
  • Volume plus separate bass and treble controls,
  • BFO pitch control,
  • An RF gain control,
  • An antenna trimmer, which is really a very basic and not particularly effective impedance matcher (SW2-8 only),
  • Three switches for wide/narrow bandwidth, AM automatic noise limiter, and AM/SSB mode switch
  • Three switches for on/off dial lights, on/off digital display, and S-meter/battery level
  • Small signal strength and battery level meter
  • A small fingertip calibrator to correct any digital frequency display error (SW2-8 only)




On the back of the rig are:
  • FM antenna terminals
  • AM/SW1 antenna/earth terminals
  • SW2-8 antenna/earth terminals
  • SO-239 coax antenna jack
  • 12-volt DC input jack
  • AC input jack
  • MW ferrite antenna that swings down and out. (An additional longwave ferrite antenna was also included for European models only)



As there is only a medium wave ferrite antenna attached, listening to shortwave requires an external antenna. Fortunately, you do not need a large antenna for this radio to come alive with lots of signals! Even just 2-3 meters (6-10 feet) of wire will do the trick!

Click on the image to enlarge.



These radios are double conversion superset designs. The block diagrams for the two models are identical, and the circuits have just minor variations:
  • DR-48: 5 ICs, 3 FETs and 34 transistors
  • DR-49: 4 ICs, 3 FETs and 39 transistors
Their published performance specs are almost identical.

Click on the image to enlarge.



The power options on these receivers allow for much flexibility: plug-in AC for home use, 12v DC from any external power source, or internal battery operation from eight "D" cells that are inserted into two compartments, accessed by flipping the radio upside down. By keeping a careful eye on power usage through the dial lights on/off and digital display on/off switches, using headphones instead of the front speaker, and periodically checking the meter for battery condition, you can get hours of operation from these big radios on the internal D-cell batteries.

If you like servicing your own radios, you will find plenty of room to play around inside this case. Once you extract the multitude of screws from the outer cabinet covers, servicing is relatively easy to undertake, even for big hands! Some long-time users have found that the band sector switches often wear out and other switches or knobs can become noisy. Alas, there is not a quick fix for these issues - getting to these components will take considerable time and patience. If the vacuum fluorescent digital display is burned out or broken, you will have difficulty finding a replacement part. Doing an alignment will take time as there are many test points to check.

So how do the RF4800/4900 (DR-48/49) receivers perform? Well, based on my own experience of both receivers, they stack up very well against other tabletop radios from that era. In the areas of sensitivity and selectivity, both radios are excellent, hearing the same shortwave signals as most other rigs of similar vintage. When used correctly, adjustment of the separate RF gain control is excellent in reducing the noise floor if listening in difficult band conditions i.e. backing off the RF gain a little can allow much better signal readability. The radio responds well to all sizes of antennas, and I have not experienced any overload when attaching a large antenna. While there are quite a few knobs and switches on the front panel, operating these rigs is easy, flexible and fun. The front-facing speaker offers good sound quality.

But not every radio design is perfect, and the RF4800/4900 (DR-48/49) series is no exception.  Strangely, receiver drift on some units appears to be worse than others. This radio works best in AM mode. Resolving SSB signals is problematic and fiddly with a very touchy BFO that is only exacerbated by the drift issue. Trying to employ a technique such as exalted-carrier selectable sideband (ECSS) to improve signal readability without a rock-steady internal carrier is an exercise in futility on these rigs. And if you want to use the radio for listening to hams and utilities, I'd advise that you look elsewhere. 

For decades, Panasonic has been a giant global distributor of consumer electronics. So, on the used receiver market, these big RF/DR rigs (in their various model versions) can be found fairly easily around the world. For a unit in excellent cosmetic condition and working well, expect the starting price to be around AUD $225 (USD $150).

Am I happy this DR-48 landed on my radio desk (....along with all the other radios 😁)?

I sure am! 

It's a cool-looking rig, I'm having lots of fun playing with it, and its solid performance is such that it is worthy of keeping in the shack. In addition, I am looking forward to taking it out for some "in-the-field" DXing in the Aussie bush. But, I will just need to make sure I have a good-sized picnic table to set it up! 



Here is a short video that shows the receiver in operation and some of its features:





FURTHER READING AND VIEWING:

Look Inside This Radio Receiver! The Collectible Panasonic RF-4900

Panasonic RF-4900/DR49 - Restoration Project

DR-49 Operating Manual

DR-48 Service Manual

DR-49 Service Manual

UPDATE: Something for the movie buffs amongst you! Our co-author of the Retro Review series, Craig Seager VK2HBT, reports spying an RF-4800 in The Bourne Legacy (2012)! Great catch there, Craig!
73 and good DX to you all,

Rob Wagner VK3BVW



 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










CLICK HERE for VK3BVW Live Stream (Clublog)



QRZ callsign lookup:


© Rob Wagner, Mount Evelyn DX Report, and contributors 2012-2023

Comments

  1. AnonymousOctober 21, 2022 at 2:10 PM

    What a nice review, thank you. I have just purchased a rf-4900, European version, and will collect it next week. Full of anticipation 😁.

    ReplyDelete

Post a Comment

Comments are moderated and may not appear immediately. If your comment isn’t visible right away, it has been received and will be published shortly.

Popular posts from this blog

RETRO RECEIVER REVIEW # 21 - The Kenwood R-5000

Image
RETRO RECEIVER REVIEW #21 (You can click on all photos in this article for a close-up view) KENWOOD R-5000 Performance and Innovation by ROB WAGNER VK3BVW This extended blog post first appeared as a feature article in the February 2024 issue of The Spectrum Monitor magazine. Further details on this excellent publication are available at www.thespectrummonitor.com I have always wanted to own a Kenwood R-5000 receiver. Perhaps I was dazzled by the mystique that appeared to surround this rig. Somehow, it had always been on top of my bucket list of pre-loved rigs that I wanted sitting on the desk of the radio shack.  Finally, one showed up at a local Sunday morning Hamfest, and I happened to have just enough dollars in my pocket to make a purchase. It appeared to have lived a hard life. The case looked knocked around and was pretty dirty inside and out. So, while I would have liked to have owned a unit in better condition, the price was right, and I decided to take it on as a l...
Read more

REVIEW: WELLBROOK ALA1530S+ LOOP ANTENNA

Image
PRODUCT REVIEW: WELLBROOK ALA1530S+ LOOP ANTENNA by Michael Stevenson (Guest Contributor) This is a review and my opinion of the Wellbrook ALA1530S+ P–1 Active receiving Antenna. For further information, details and specifications then please visit: www.wellbrook.uk.com Background I have been a keen shortwave listener since 1970 and have had many receivers and antenna types during this time. Currently I have two wire antennas, a PAR Electronics EF-SWL 15 meter with impedance matching transformer, made in the US; and a home made 17 meter wire with balun. I also have a dedicated multi-stake ground or earthing system to compliment my receiver and antennas. I live in suburbia Port Macquarie, New South Wales on the east coast of Australia. Even though all our electricity wiring is under ground in our housing estate, I live in an environment where there are all types of man-made noises coming from modern electronic and electrical equipment used by my neighbours The wire a...
Read more

RETRO RECEIVER REVIEW #20 - The SONY ICF-5900W

Image
RETRO RECEIVER REVIEW #20 SONY ICF-5900W by CRAIG SEAGER VK2HBT This time around, I thought we might direct our attention to one of the many portable receivers of yesteryear, and it is perhaps appropriate that we choose a manufacturer that continued to produce quality equipment featuring shortwave coverage until long after. I’m sure our Japanese friends will concur with the submission that Japan is a land of short-lived, but enthusiastically embraced fads.  Whether it be karaoke, yo-yos with brains, electronics pets or Pokémon, each craze sweeps the country in such a way that captures the attention of the rest of the world and is usually associated with some pretty smart home-grown technology.   In the mid to late 1970s, shortwave listening (or “BCL”) was the flavour of the month, with teenagers (and some older folk!) compiling large QSL collections and forming SWL and DX clubs all over the country.  Nowadays, you’d be fairly hard-pressed to find any external broadcas...
Read more