Mid-Atlantic Antique Radio Club - MAARC

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Mid-Atlantic Antique Radio Club - MAARC The Mid-Atlantic Antique Radio Club (MAARC) is a hobby club for those dedicated to collecting, restoring, and preserving vintage electronics. Join MAARC!

MAARC is a club for those dedicated to collecting, restoring, and preserving vintage electronics, including radio, television, hi-fi, vacuum tube, electronic test equipment, tube audio, and yes, vintage computers and computer games. Collecting antique radio, television, hi-fi audio/stereo, electronic instruments, and test equipment is a fun and interesting pastime that appeals to a variety of folks. Members include pure collectors who are looking for their next great find, technicians and tinkerers who like to restore the electronics or refinish cabinets, historians and preservationists interested in the history of the technology, and those who are into it as a small business. Many involved dabble in several of these areas. All enjoy the camaraderie of a shared interest. You will find vintage electronics collectors to be a friendly and honest group who do not take themselves too seriously, while recognizing they are preserving a part of our heritage. How Will MAARC Benefit Me? MAARC meetings and our Radio Age journal provide presentations and articles covering all aspects of our interests in vintage electronics. This covers everything from repair techniques, to cabinet refinishing, to test equipment, to tube collecting, to electronics history. Looking for a little fun? MAARC members enjoy hanging out with techies who share similar interests and pas-sions. We hold a banquet and restored equipment contest at our annual RadioActiv-ity event. MAARC Offers You the Opportunity to Buy or Sell Vintage Electronics. All MAARC meetings feature a flea market tailgating period and an auction. Both provide the opportunity to buy and sell old radios, hi-fi audio, ham equipment, tubes, vintage electronics parts, service equipment, and literature at good prices. Monthly meeting tailgate sales are without any fees. Auction buyers pay no fees, while sellers pay just a small commission. Of course, there is no guarantee that all items will sell, though most do. The monthly auctions tend to be more informal, with no minimum bids and often, no reserves. Because of the prices typically realized, the monthly auctions tend to be good opportunities to buy and sell lesser quality items and parts. Twice a year we offer larger meets with bigger flea markets and auctions. These larger auctions have higher quality offerings and are more likely to garner better prices. They may have minimum opening bids, consignment limits, and other policy requirements to help manage the auction. These two events, RadioActivity and RadioFallFest, are normally in June and October respectively. Guests are invited to our monthly 3rd Sunday meetings in Davidsonville, MD (Feb, Mar, May, Jul, Aug, Sep, & Nov) or Centreville, VA (Apr & Dec). Tailgate sales for these events start at 11:00 AM, with the meeting, including a Show and Tell and a topical presentation at 1:00 PM. This is followed by an auction of a wide variety of vintage electronics. Our October Fallfest in Davidsonville kicks off at 7:00 AM with a huge auction at noon. Other events include our January Winterfest at the National Electronics Museum (NEM) in Linthicum, MD near BWI airport, and our 3-day RadioActivity event held in June at a conference facility within the DC/Baltimore region. MAARC members receive monthly issues of our vintage electronics journal Radio Age (containing interesting and in¬formative articles), on-line access to past MAARC Newsletter and Radio Age copies and to the club's members-only Internet discussion forum. If you are a member of either NEM or the National Capital Radio & Television Museum (NCRTV), you get a onetime first year MAARC dues discount ($20 vs. $24). MAARC created NCRTV, which offers photocopies of service literature at low cost (see NCRTV.org.) For additional information, visit our website:
WWW.MAARC.ORG

On this Sunday, 11 October, the MAARC Facebook post is, you guessed it, another quiz. But first, an announcement. We are...
10/11/2026

On this Sunday, 11 October, the MAARC Facebook post is, you guessed it, another quiz. But first, an announcement. We are running out of quizzes on or about vintage electronics, and we need your help. Do you have a vintage electronics quiz contribution? It can be an entire quiz, or just a question or two. If so, we would really enjoy sharing that. To submit your quiz inputs, go to the https://maarc.org/ website, and send it to either the webmaster or 'Contact' email address.

This week's quiz is entitled "Inventors & Their Inventions" that vintage electronics enthusiasts just might know off of the top of their heads. Let's see how you do. Submit your answers as a comment.

1. Who is credited with inventing the computer mouse?
a) Bill Gates
b) Steve Jobs
c) Bill Nye (the science guy)
d) Douglas Engelbart

2. Who is credited with discovering the transistor?
a) John Bardeen
b) William Shockley
c) Walter Brattain
d) All the above

3. Who invented the Viterbi programming algorithm?
a) Andrew Viterbi
b) Robert Pease
c) Albert Einstein
d) Robert Lucky

4. Who is credited with inventing the triode amplifier vacuum tube (Audion)?
a) Sir Jonathan Audion
b) James Watt
c) Brian Koenigsmark
d) Lee De Forest

5. Who invented the tunnel diode?
a) Scott Adams
b) Leo Esaki
c) Patrick Fitzgerald
d) Igor Stravinsky

6. Who is credited with inventing spread spectrum communications?
a) Akio Morita
b) Thomas Steenland
c) Hedy Lamarr
d) Albert Gore

7. Who is credited with inventing frequency modulation (FM)?
a) Edwin Armstrong
b) Heike Onnes
c) Robert Jarvik
d) Charlie Eppes

8. Who is credited with inventing television?
a) Yataro Iwasaki
b) Lothar Rohde
c) Hermann Schwarz
d) Philo Farnsworth

9. Who is credited with inventing radar?
a) Gordon Gould
b) Elmer Sperry
c) Sir Robert Watson-Watt
d) Augustus Raytheon

10. Who is credited with inventing the first integrated circuit?
a) Garrett Morgan
b) Jack Kilby
c) James (Jim) Wilson
d) Grace Hopper

Honorable Mention will be awarded the high scorers.

RadioFallFest 2026 Vintage Electronics Expo October 18 @ 8:00 am - 4:00 pm EDT Davidsonville Family Recreation Center 3789 QUEEN ANNE BRIDGE RD., DAVIDSONVILLE, MD, United States Our second biggest event of the year. Flea Market Gates Open at 8:00 a.m. Walk-around Auction at 11 a.m. Main Auction at....

The Saturday, 10 October MAARC Facebook post provides some additional Catchup related to our series on 'how a vintage ra...
10/10/2026

The Saturday, 10 October MAARC Facebook post provides some additional Catchup related to our series on 'how a vintage radio works,' but first this this News Flash from the National Capital Radio & Television Museum. The museum, which was established over 30 years ago primarily by MAARC members, is excited to share a recent video from Podcaster Stephen Moore!

The first half of the 45-minuite YouTube video podcast features video snippets of our very own Museum Curator Brian Belanger giving Moore a tour of the National Capital Radio Museum. The second half is an interview that Moore did with beloved local radio personality Ed Walker (the Museum’s first board chair) about his radio career and how he started local station WAMU. Enjoy funny stories about Ed and his partner Willard Scott when they were “The Joy Boys” on radio. Here is the link to the video: https://www.youtube.com/watch?v=h3o_F9kWFuw

Back to the Catchup. On 12 September we had a post that addressed that although the 'neutral' wire and the 'ground' wire of a wall outlet are connected at the breaker panel, you should never use the 'ground' as the 'neutral.' David Dodgen, a long-time electrician, had this to share: 'I just want to point out that the box where the ground and neutrals are combined in the same buss is only in the Service Panel. Not in the Distribution, Load panels. This is in the National Electric Code (NEC). The Service Panel is the first point of service drop where the ground rod is also connected. Thereafter grounds and neutrals must be separate. In some installations the only panel is the Service panel, because the distribution is not extensive. So as not to be critical, this is easy to be confused, and is lost to most homeowners who do wiring."

On 24 September we had a discussion on radio power supplies, and how the vacuum tube filaments in the All American Five (AA5) radio are connected in series, eliminating the need for a power transformer. Carl Henry posted these "subtle points about this circuit: The order in which the heaters are connected is important because there is some leakage between a tube's cathode and its heater, which produces hum. The 12SQ7 is the first audio tube and most susceptible to hum, so its heater is placed nearest neutral. Conversely, the 35Z5's cathode is close to hot, so its heater is at the top of the string. The 50L6 is next least sensitive to hum, so its heater comes after the 35Z5, and the converter and IF tubes are in the middle. Also, there can be a significant voltage difference between each tube's cathode and heater, requiring suitable insulation. Except for the 35Z5, each cathode is only a few volts above neutral, but the top of the heater string swings between +/-170 volts. Finally, all the tube heaters must have matching warmup characteristics, i.e., the way the heaters' resistance varies while heating up, or else voltage distribution amongst the heaters will swing wildly during warmup, leading to early tube failure." Thanks for sharing those points Dave and Carl.

Here was an interesting post: Gerhard E. Jene stated "While it is nice to try to keep these antique units running, once a tube dies, the unit is almost certainly scrap unless modified. Is there no way of using today's technology inside the respective tube to recreate the function of the tube? That way the old radio can still be used and in some cases enjoyed instead of collecting dust or disposed of."

Now, interestingly, it is very rare that the tube needed to repair almost any radio is not available. There are many reasons for this. First off, unlike light bulbs, most tubes were not used for long periods. The vast majority of tubes tested today, ev,en those that have been pulled from old sets, still show life. Now, don't get me wrong, tubes do short out, wear out, leak gas, or otherwise die. But the amazing thing is that many still test good. I have tested tubes that are identified as being true antiques, having been manufactured over 100 years ago, that still test as good. With regard to the AA5, there were so many of those radios that used the same tube lineup, they are all still readily available.

But Gerhard did bring up a good point regarding the replacement of tubes with modern solid state components. This has been done. In fact, last October 25th and 25, we had a two part post on " POWER FET REPLACEMENTS FOR ANTIQUE RADIO TUBES." There are also solid state replacements and equivalents available for key Zenith TransOceanic radio tubes. Most notably for the rare and expensive 1L6 converter tube and the 50A1 ballast tube. Long time MAARC member Robert Lozier had this to say in response to the comments we had on solid state tube replacements. "I try to fill all my 20s vintage radios with working tubes of the proper vintage.... That is not much of a problem for me when it comes to Type 201-A tubes. But UV and UX-199s are a whole 'nother thang! Less than half of my sets have working 199s That is why I'd like to "fix them" by adding some sort of semiconductor circuit small enough to be attached to the base of the tube. Don't know if there is a practical way of hiding the "fix" inside the base or whether it could be tucked up against the base on the outside. Does anyone know if the cement used on RCA or Cunningham tubes of the 20s can be soaked enough to loosen and extract the bulb from the base?"

Where can you purchase vacuum tubes? We have identified a number of sources on the "Sites & Resources" page on our website (https://maarc.org/radios/). Look for the heading "Vacuum Tubes."

We had some comments that show folks are enjoying the series. Khawja Aziz posted "Excellent.. Thanks for sharing." Barry Dorr stated "Excellent article. Please keep them coming!" Philip Stephen Crosby easily identified that "The vacuum tube with the heaters in series adding to the 120 V line were called the "All-American Five"." and we even had a post in Traditional Chinese, made by Jose Wang Mao. Luckily, Facebook translated it for us. It read "Five-light machine without a power transformer." Now we know what the AA5 is called in China.

Thanks for all the comments and posts. They help us to better understand the vintage electronics hobby.

Step inside the National Capital Radio & Television Museum with Cap...

For the Friday, 9 October MAARC Facebook post, we continue with our series on how a vintage radio operates. We have had ...
10/09/2026

For the Friday, 9 October MAARC Facebook post, we continue with our series on how a vintage radio operates. We have had a slew of comments, many of which add value to our understanding. So, let's see what folks have had to say.

We had an ongoing discussion regarding GFCI (Ground Fault Circuit Interrupter) circuits that is worth commenting on. First, a little background on GFCIs.

A Ground Fault Circuit Interrupter (GFCI) works by constantly comparing the amount of electrical current flowing through the hot wire and the neutral wire in a circuit. Under normal conditions, the current going into an appliance through the hot wire must equal the current returning through the neutral wire. If electricity escapes the circuit through an unintended path—such as through water, a damaged wire, or a human body (a Ground Fault Leak)—a tiny amount of current is lost. The GFCI measures the difference between the outgoing and returning current, and have a 5-milliamp threshold. If it detects an imbalance as small as 4 to 6 milliamps, it senses a ground fault. Within a fraction of a second (about 25 to 100 milliseconds), an internal solenoid or relay mechanically trips the contacts and cuts off the electricity, preventing a fatal shock.

There are three types of GFCIs. GFCI Receptacles are installed in place of a standard wall outlet. It features test and reset buttons on the face and can protect devices plugged directly into it or connected downstream. GFCI Circuit Breakers are installed inside the main electrical service panel to protect an entire branch circuit, including all wiring and outlets tied to it. Portable GFCI power strips plug into a standard outlet to provide temporary ground-fault safety for outdoor tools or equipment.

For safety purposes, the workbench you use for working on vintage electronics should be protected by an isolation transformer, particularly if working on an All American Five (AA5) radio. Additionally, your bench should also be protected by the use of a GFCI device. But some vintage electronics can trip GFCI devices, and we had a discussion on that subject that is worth repeating.

Steven Fox started things off with this discussion: "I have recently finished restoring the electronics of an RCA Victor 96T4 (attached Schematic - see photo) and the woodwork restoration is next. My issue is, like Ed Lyon, I like to replace the power cord with a three wire plug for safety reasons. This is the first radio I have not been able to ground the chassis. At my work bench all my power receptacles are GFCI. When I try grounding the chassis the GFCI trips. I look at the schematic and there is obviously some current going through R11, thus tripping the GFCI. When the 96T4 radio was invented GFCI’s were not available. Are you aware of a fix?

My thoughts. Because of R11 in my radio, it’s like the chassis’ voltage is allowed to float more negatively below the “Common Negative Line” voltage as “true ground” is only available through C3. It looks to me, as 96T4 is engineered, when there is no current flowing through R11 the same voltage can be measured at the chassis as on the “Common Negative Line,” which is a ‘slight’ shock hazard if one was to touch the chassis and “true ground” at the same time.

Also, I also noticed that due to the 96T4’s C29 (near the plug) with the radio plugged in and the switch is off you can register 120 VACS on the Common Negative Line to ‘ground’ (the ‘hot’ side is not switched). Again no current flowing because of the capacitor, but it does seem one can get a short bite from the discharge of C29 if one is not careful. I am curious as to what you think.

My response was "You are leading into topics I will be covering within the next two weeks, mainly where the on/off switch should be relative to the use of a polarized plug, and line filter capacitors, such as your C29. I think you will find them useful from a safety perspective.

That said, Ed Lyon, having read your post, had this to say: “What you are seeing is the leakage of a-c voltage to the chassis, even though the deliberate pathways offer only a milliamp or two via actual resistors, they get some additional leakage from other pathways from the neutral to the chassis. When the total exceeds, theoretically, 5 milliamps, the GFCI will trip, as it is monitoring the difference in a-c current between that in the black (“hot”) wire and that in the (neutral) white wire, and if it exceeds 5 mA, it trips the GFCI breaker. But I have seen them fail to trip at 8 or 9 mA, and some that trip at 3 mA.

The leakage he is talking about is something that is getting to be pretty common with regard to vintage electronics in general. Let’s face it, your radio from 1939 is over 85 years old. Even though your radio does not have a power transformer, the windings in all those coils within your radio can very well be leaking low level amperage. Hickok came out with its 539C tube tester 19 years after your radio in 1958, and many of its power transformers are now found to be leaky.

Ed Lyon went on to say "The schematic diagram you included for the RCA 96T4 shows a total of 0.2 microfarads from the “common negative line” to chassis [through the .1 MFD C37 and the .1 MFD C25]. This amounts to approximately 13,000 ohms reactance. At 120 volts a-c at 60 Hz, that means about 9 milliamperes current flow from one side of the power line to chassis, whereas any leakage above 5 milliamps should trip the GFCI. I believe the two 0.1 uF capacitors, in parallel are way too much capacitance for RF grounding the common negative line to chassis. And don’t forget, that with the on-off switch wired the way the schematic shows, the HOT power wire sees the 0.2 uF to chassis when the on-off switch is OFF and the NEUTRAL wire sees the 0.2 uF to chassis when the on-off switch is ON. Never do BOTH (the neutral and the hot wire) see the 0.2 uF to chassis, which is what the GFCI tolerates feeling without making a click. Steven Fox responded "There is another .1uF capacitor (C29 near the plug) “across the line”. When the switch is open or closed I calculate the reactance to be around 40K with C25 & C29 in parallel plus C29 in series with the previous pair at 120v@60hz. I take it this setup is okay provided C29 is a ‘safety capacitor’. Also, there is a 120K resistor (R11) which also can carries current. I haven’t quite figured out why this resistor is present as it makes the chassis more negative than the “common negative line.” Any clarifications you can offer would be appreciated. By the way, I have changed the switch to the ‘hot’ side as it seems safer, and the neutral is now un-switched. I still can’t use a three-prong plug. I take it this radio is destined to be two prongs only." To this, Ed Lyon responded: "We have to remember that GFCI-type circuit breakers are prevalent and are sensitive to the difference in current between the black (hot) wire and the white (neutral) wire in the circuit fed by the GFCI device. A five milliamp difference will trip the GFCI. Now, in the schematic we see a capacitor and resistor in parallel connecting the white wire and the chassis (no-matter whether the radio switch is OFF or ON), which chassis might be grounded to actual earth by a person or by the radio’s antenna/ground connections, or if the radio has been up-dated with a three-wire power-cord improvement. Any of these conditions puts some of the white-wire current into the ground wire in that household circuit, and will trip the GFCI. A capacitor of 0.1 uF is about as much capacitor as the GFCI will stand in unbalance between black and white wires. So that size is the maximum size of that capacitor (Neutral-to-chassis) that can be tolerated. It would be better to make that capacitor half that size or even smaller, and be a fail-open type."

My takeaway from this GFCI discussion is that line filters, which are in place to reduce interference coming in from multiple sources across the power line, can trip the GFCI. Smaller valued safety capacitors may be substituted. These may work just as well as the larger capacitors for reducing the interference, and additionally keep your GFCI protection device from tripping.

We will follow up with more 'how a vintage radio works' Catchup tomorrow.

The Thursday, 8 October MAARC Facebook post comes to us from the December 1993 "MAARC Newsletter." Entitled "EMERSON AND...
10/08/2026

The Thursday, 8 October MAARC Facebook post comes to us from the December 1993 "MAARC Newsletter." Entitled "EMERSON AND INGRAHAM," it was written by long-time MAARC member Brian Belanger, based in part on material provided by Barry Cheslock.

"Many radio collectors concentrate on radios from one manufacturer. While I have lots of different brands in my collection, I am particularly fond of Emersons, and have more of them than any other kind. Why? Because I am fascinated by the exotic wood cabinets that Emerson featured during the 1930s, my favorite period. While other manufacturers made tombstones and cathedrals that tended to look pretty much alike, Emerson tended towards the unusual. Other companies used simple speaker cutouts with grille cloth, but Emerson employed in many models wood speaker baffles characterized by swooping curves and circles. (Figure 1. Emerson Model DB-315, with curved wood speaker baffle - see photo.) (Figure 2. AX-series "Little Miracle" set, only about 5 1/2" tall, with wood speaker grille - see photo.) (Figure 3. Emerson Model R-167. The curved grille area is typical of Ingraham cabinets of the late 1930s - see photo.) Emerson made the famous "Mae West" radio (see photo), radios with curved sides like the Model U6F (Figure 4. Model U6F. Ingraham cabinets used curved sides much more frequently than other makes - see photo.), and unusual models with cabinets in the shape of violins (the "Strad" - see photo).

I am not aware of anyone who has done a comprehensive history of Emerson, and I would welcome correspondence with anyone who has researched this company. For some unknown reason, very little has been written about this company, even though they were a major manufacturer.

According to the book Small Radio, published by Emerson in 1943, the Emerson Radio and Phonograph Company was formed in 1924 by consolidating the Emerson Phonograph Company, Inc. and the Emerson Radio Corporation. Prior to that, the Emerson Phonograph Co. had established a solid business, having sold thousands of phonographs and millions of records.

During the 1920s, Emerson remained a relatively minor player in the radio business. However, early in the Depression, they found their niche and began to make inexpensive radios in small cabinets. In the right place at the right time, their sales increased steadily throughout the '30s while other radio manufacturers were going bankrupt in droves. They were one of the first companies to market successfully a very inexpensive compact ac/dc set (Model 25 - see photo), and were also among the first to use Bakelite cabinets. By 1941 Emerson was selling almost 1.2 million radios per year and had 17.5 percent of the market.

A great many radio manufacturers of the 1930s contracted out the manufacture of wood cabinets to furniture companies. Emerson engaged the E. Ingraham Company, a well-established New England clock-making firm, and Ingraham made many of Emerson's most interesting wood cabinets.

It is not clear exactly when Emerson began using Ingraham cabinets, but it may have been when Emerson introduced the Model 25. In Small Radio, Benjamin Abrams, president of Emerson in 1943, said the company had been impressed with the success of the inexpensive "midget" or "mantel" sets made by a variety of small companies in the Los Angeles area during the 1929-1931 era. He felt that it ought to be possible to do even better in terms of sizing down. He describes the development of the Model 25 as follows:

"In 1932, when the fortunes of small radio were at their lowest ebb, I found what I was looking for and what later pointed the way to a successful operation. It was a clock, or rather a clock case--handsomely styled as style was understood in those days, and only ten inches wide, six and a half inches high, and four inches deep. The idea of squeezing a radio chassis, complete with speaker and tubes into a case of such dimensions was, of course, preposterous."

Abrams noted that his engineers had to develop miniaturized (for that era) tuning capacitors, coils, dials, and other parts in order to shoehorn the works into a clock case. The Model 25 chassis, which was available in a couple of different wood clock- case cabinets as well as a Bakelite cabinet, was a four-tube receiver with a six-inch speaker. When most other radios were designed to use a long-wire outside antenna and a good ground, the Model 25 used a hank of wire that could be unrolled behind the sofa or under the bed. It weighed only six pounds when other "midget" sets tipped the scales at 25-30 pounds. It listed for $25. According to Abrams, more than 200,000 of these compact sets were sold during the 1932-33 period.

Abrams doesn't say that the clock case that inspired him to develop the Model 25 was made by Ingraham, but that seems likely because it was about that time that Emerson radios began appearing in small wood cabinets with a metal plate on the back indicating that the cabinet was "Made by Ingraham."

Emerson's success in making small inexpensive radios that performed fairly well helped to change people's thinking about radio. Instead of visualizing a radio as a large highboy piece of furniture destined only for the living room, or a heavy cathedral or tombstone that required a sturdy table to support it, people could now imagine a radio on a bedside table or a kitchen shelf. Emerson also was one of the first companies to create successful novelty radios specifically intended for a child's bedroom, such as the 1933 Mickey Mouse radio (see photo) and the similar Snow White model (see photo).

Barry Cheslock, an Emerson-Ingraham aficionado, recently wrote to Stuart Mitchell, curator of the American Clock and Watch Museum in Bristol, CT, seeking information about Ingraham that would shed light on its connection with Emerson. Mitchell pointed out that during the 1930s, Ingraham was eager to expand its business and branched out into making humidors and veneered cigarette cases. Their arrangement with Emerson was probably their most successful venture outside of their normal clock business. Ingraham's 1938 catalog featured two pages of Emerson radio cabinets. However, Mitchell was unable to locate any information regarding when precisely Ingraham began making cabinets for Emerson or when the relationship ended.

The styling of 1930s Emerson console cabinets is very similar to that of their small table models made by Ingraham, which suggests that Emerson consoles could also have been designed and made by Ingraham. But a page from a 1938 Ingraham catalog stated that Ingraham had "facilities for designing and producing high grade cabinets in sizes up to but not exceeding end table radio models." This certainly suggests that someone other than Ingraham made Emerson's large console cabinets. I wonder who?

Today you can buy consumer electronic products with the Emerson name and treble clef logo, but don't be fooled. Years ago an overseas company bought the rights to use the Emerson name and logo, and there is no connection between today's Emerson products and those marvelous old Emerson radios pictured in this article.

If you have any additional information on Emerson and/or Ingraham, do share it with us!"

Well, a Google search revealed that there is no major, dedicated standalone book published about the corporate history of the Emerson Radio Corporation. Instead, the history of the company—founded in 1915 by Victor Hugo Emerson as the Emerson Phonograph Co. before being taken over by Benjamin Abrams and transitioned into radios Emerson Radio Corp. is typically documented across broader consumer electronics and vintage radio literature. Books like "The Portable Radio in American Life" by Michael B. Schiffer explore Emerson's vital role in producing compact novelty and pocket radios (such as the famous '888' transistor series). But with the help of the Internet, I was able to provide much nicer photos (than the black and white ones in the newsletter) of all the specific radios Brian addressed.

The Wednesday, 7 October MAARC Facebook post comes to us courtesy of the "At The Controls" page and Michael Tal...
10/07/2026

The Wednesday, 7 October MAARC Facebook post comes to us courtesy of the "At The Controls" page and Michael Talbot.

UNIVAC II¹ computer (Lockheed Aircraft Company², Marietta, Georgia 1960s) Jet propulsion engineer Emma Davis (see photo) working on a series of MATH-MATIC programs³ simulating gas dynamic⁴ combustion models⁵ of Pratt & Whitney TF33 turbofan engines⁶ powering Lockheed's new Model 300 prototype aircraft, which is now better known as the Lockheed C-141 Starlifter⁷.

This 72-bit (twelve 6-bit characters) serial computer made by Sperry Rand in 1959 was an improved, compatible version of their UNIVAC I. Its 2.25 MHz clock gave it a slightly faster speed of 3000 operations per second, powered by 5,200 vacuum tubes consuming 190 kW, and yet was also partially solid-state with 1,200 transistors, 18,000 Crystal diodes, and a 184,000 bit reliable ferrite core memory⁸, a tenfold memory improvement over the mercury delay-line tanks⁹ of the previous incarnation of UNIVAC. It also included the new UNISERVO II tape drives¹⁰ capable of using the more robust BoPET polyester film tapes. MATH-MATIC was the marketing name for the AT-3 (Algebraic Translator 3) compiler written by Grace Hopper¹¹ and was an early UNIVAC II scientific programming language that influenced the creation of ALGOL 58¹².

Footnotes
1. https://en.wikipedia.org/wiki/UNIVAC_II
2. https://en.wikipedia.org/wiki/Lockheed_Corporation
3. https://en.wikipedia.org/wiki/MATH-MATIC
4. https://en.wikipedia.org/wiki/Compressible_flow
5. https://en.wikipedia.org/wiki/Combustion_models_for_CFD
6. https://en.wikipedia.org/wiki/Pratt_%26_Whitney_TF33
7. https://en.wikipedia.org/wiki/Lockheed_C-141_Starlifter
8. https://en.wikipedia.org/wiki/Magnetic-core_memory
9. https://en.wikipedia.org/wiki/Delay-line_memory
10. https://en.wikipedia.org/wiki/UNISERVO_I
11. https://en.wikipedia.org/wiki/Grace_Hopper
12. https://en.wikipedia.org/wiki/ALGOL_58

Reference
A few good men from Univac by David E. Lundstrom 1987 227p
https://archive.org/details/fewgoodmenfromun00lund

Additional Michel Talbot Addendum:

Early computers did not have much software already written, so computer users often had to flowchart their own programs (see photo).

Closeup on some console details of the UNIVAC II emphasizing the large edge-lit Lixie displays (see photo).

UNIVAC II internals (see photo).

Closeup of UNIVAC II ferrite core memory (see photo).

UNIVAC II console (see photo).

UNIVAC II Basic Programming Manual, 321 pages (13.8 MB)
https://www.bitsavers.org/.../UnivacII_Programming_1957.pdf (see photo).

A Tektronix Type 531 oscilloscope was used to troubleshoot the UNIVAC II design during final testing at the UNIVAC division headquarters of Sperry Rand (1959) (see photo).

The UNIVAC II at Lockheed used the more advanced UNISERVO II tape drives for storage (see photo).

The Tuesday, 6 October MAARC Facebook post provides some additional Catchup, but first, we need to acknowledge our quiz ...
10/06/2026

The Tuesday, 6 October MAARC Facebook post provides some additional Catchup, but first, we need to acknowledge our quiz winners. Honorable Mention for the Electronics Physics Quiz goes out to John Foell for a 10 out of 10 score.

On 17 September we had a post that addressed the Gibson Girl Emergency Communications Radio. Mike Murphy posted "Watch the John Wayne movie “Island In The Sky” to see it in action."

On 19 September we had a post about AM radio station WBT that is shutting down. It got quite a number of responses. Christopher Wideman told us "I recorded WBT 1110 on my CC Skywave SSB [manufactured by C. Crane Company] this past Wednesday September 16, and the loop is still playing. There were some soothing songs I love during the repetitive loop. I recorded WBT AM for an hour and a half from Greenwood, SC." William Coffman posted " They don't realize that the internet/streaming can go down but an AM signal will always be there." John C Wise stated "So sad AM radio stations are being shut down in favor of short range FM. Some day they will wish they had coverage over thousands of miles. Most all the AM stations where I live emphases their Low Power FM frequency over the AM frequency, which does not cover as much area as their AM frequency. In the UK, the Long Wave station BBC went off the air this year and that could be heard here in the East coast of America." Robert Lozier, who lives in North Carolina had this for us "Minor correction.... According to a Charlotte News article, WBT signed-on in March 23, 1922. But the license is dated April 1922.... Power about 100 Watts. Claimed that their broadcast had been heard 1,000 miles away. Only one terrible newspaper photo of the transmitter. Table top rig. Had 'slop jar' chemical rectifiers for B+ on the floor. As with many stations of the day, was on the air for a few hours at a time and maybe two days a week. By 1927 they were on the air through much of the day and early evenings and had a line to a chain of stations." To conclude,
Ed Lyon filled in some additional blanks "WBT was on 1110 kHz by 1942, but started out at 830 kHz (actually 360 meters wavelength) originally, as listed in 1923. The 1926 logbook shows WBT at 1090 kHz ~275 meters wavelength, so that antenna would have worked pretty well on all of those frequencies, needing a little change in loading coil for each change."

On 23 September we posted about the WWII Navy WAVE Telegraph Operator. John D. Foell posted "Way cool pictures (see photos). What amazes me is how those old-time operators could wear those ear killing headphones for hours. They also had immense powers of concentration to be able to pick signals with low (less than 3 dB) signal to noise ratio (SNR) out of the background noise. When I worked in radio design the various sets we made did a lot of the setup / antenna pointing (Tactical SATCOM) / INFOSEC codes and waveform setting / etc. automatically with just a few inputs from the operator. Lots of software and firmware to make the operator's job easier. I was a "nuts and bolts" RF guy (synthesizers, receivers, modulators, etc.) so some of the setup magic did seem a bit like magic to me. Closest I got to it was writing tuning algorithms which were implemented by the software / firmware folks."

On 26 September we had a post about THE DRAKE FORMAT, used by various disk jockeys over the years that raised station ratings. Robert Souza addressed Bill Drake's move to KSTN: "No hate. Both KSTN & KYNO were offered together with a car and an apartment in Fresno. The combination of the 2 stations plus the perks equaled or surpassed the money Bill was making at KYA. MAARC cofounder Joe Koester gave us this: "I enjoyed the post on Disc Jockeys and it brought back some memories for me.

When I was in the Air Force I spent a tour at Shemya Air Force Station on Shemya Island (see photo) very near the end of the Aleutian Island chain. We were actually closer to Japan than Anchorage, and Russia was next door. To call it a remote assignment is an understatement. The island was 2 miles wide and 4 miles long, with a girl behind every tree – unfortunately there wasn’t a tree on the island.

To help pass the non-duty time away I became a disc jockey on AFRS (Armed Force Radio Service) Shemya. Two turn tables, a console, a R-390 receiver, and a room full of records, many dating back to WWII. So I spun records and drank b**r. Shemya was called the Black Pearl of the Aleutians and I was known as “The Golden Voice of the Black Pearl.” At least in my own mind.

When propagation was right we did occasionally get out and one night we got a phone call from Seattle requesting a song. I am sure our neighbors 225 miles to the west enjoyed the music but they never called and I didn’t speak Russian.

At the top of the hour we were instructed to tune to AFRS in California on the R-390 to pick up the world news and retransmit it locally. I was listening to the news broadcast in the background and started hearing about the bad capitalists and Americans and found I was feeding Radio Moscow into our transmitter. I quickly terminated that and started spinning records again. I recoded a lot of my music on a tape recorder and would have rock and roll or country or whatever the entire broadcast. Feedback suggested that I not do that again. We had a very strong FPS-17 radar (see photo) on the island and most of my music had the radar’s PRF (Pulse Repetition Frequency) in the background, but after a while you got used to it.

One night an Army buddy joined me at the station and brought a case of b**r. He also brought a small pump organ he used on Sunday morning, and after a number of b**rs we thought it was a good idea to play the organ live on the air. Needless to say the Chaplin was not amused and I suspect the NCOs in charge of the station weren’t either, but we survived.

We also received records from AFRTS in California in the mail with the hits, called “Rocketing Rhythms,” which were very well received as Glenn Miller and Tommy Dorsey were getting old. Less interesting was “Meet the Press” and a couple of other talk shows.

It was quite an experience, a lot of fun, and helped to pass the idle time. I actually got a certificate from AFRS, but alas no medal for morale. Perhaps I should have tried to join AFRS during my off duty time in Saigon a few years later, and they might have made a movie about me!" Thanks for that Joe.

On 30 September we had a post about 15 legendary hi-fi brands that are still going strong today. John Foell commented "I have one of the 50" Pioneer Plasma sets (plus 3 Panasonic Plasmas - also 50") Still like the color rendition better than my 4K OLED (Samsung). Not as bright but just truer IMHO. I also have a boat anchor of a Pioneer LaserVision player which has a helium-neon (tube) laser - I think 1978 or so. Call me a throwback but Laser Discs haven't got the room to put all the "must watches", previews, and outright commercials they put on DVDs. Resolution not as high but "logistically" the Laser Disc just nicer to use - put it in and it plays, no unwanted "extras". I must not be alone as there seems to be quite a trade going on sites like eBay."

Well, that wraps up our Catchup. I hope you all enjoy the added details as much as I do.

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Davidsonville, MD
21035

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