VOLUME 15 JANUARY 1998 NUMBER 1
RADIO MISCELLANEA -- January 1998From Antique Radio Classified for January 1998
(Copyright 1996-7 by John V. Terrey - For personal use only.)
"Antique Radio Classified" invites its readers to contribute letters and information for inclusion in "Radio Miscellanea" and elsewhere in the magazine. "In The Marketplace" is based on information submitted by the businesses themselves. All topics should be of general interest and sent to A.R.C., P.O. Box 2, Carlisle, MA 01741. All material submitted should be verified for accuracy and may be edited for publication, which is not guaranteed. See the masthead for more details.
On Bruce Kelley Tribute
All of us who are involved with the activities of the AWA wish to thank you for the fine article on Bruce Kelley. This is much appreciated as A.R.C. saw fit to let its subscribers know that Bruce was so very important to the radio collecting fraternity.
--Lauren Peckham, Breesport, NY
Superb December '97 Issue!
Although always anticipated, devoured, and enjoyed, the December issue of A.R.C. was one of the best yet. Applause for the article on and review of the latest Cones and Bryant Zenith book. Dick Desjarlais convinced me that I must have both the Bunis fourth edition and the Bintliff Foto Finder. I found particularly poignant the story of Joseph Jackson's efforts to save his grandfather's Columbia 31. With sadness I read of the passing of Bruce Kelly -- a gracious and charming gentleman. Even the short article by William Miedema touched a nostalgic nerve because my parents' first post-World War II radio was from Electronic Laboratories Co. I await the next installment of Ray Bintliff's article on capacitors, although I thought his Figure 4 could use another layer of dielectric material. [Yes, Dale, there should be a dielectric for each foil -- we "simplifieth" too much!]
Concerning newsletters vs. club journals, I respectfully take a tangential stand to that of my friend Gerald Schneider. I personally would like to see as many publications as possible, ideally with some sort of central collection point for reference and research. All too often historical information is preserved only through small publications with limited distribution.
From the ads, I sold one and bought one, so here too I prospered!
To everyone behind A.R.C.'s preparation and distribution: Take a handful of "Attaboys" out of the till -- you've earned and deserve them!
--Dale Davenport, Fort Smith, AR
On Post Office Mailing Mysteries
I am enclosing a check for $111.90 for another two years of Antique Radio Classified by First Class mail. First Class mail is much better than Periodical Mail by which the other ten magazines I receive are sent. For example, I received the October 1997 issue of the magazine Nuts and Volts on October 29, 1997, mailed from California during the first few days of the month. I don't know how the post office managed to take almost an entire month to get the magazine to me -- unless someone kept it to read. One month, I received my copy of Consumer Reports with two pages stuck together with grape jelly!
--Aurie S. Myers, Jr., Lexington, NC
We're also working at keeping the peanut butter out of A.R.C. (Editor)
More on Capacitors
As a note to Ray Bintliff's excellent article on capacitors, I'd like to share some observations about mica capacitors. Molded mica capacitors with values between 10 pf and 100 pf were used by the manufacturers of many auto radios for the purpose of coupling the plate of the RF amplifier to the input of the mixer stage. Also, in addition to the diode filters in the second IF, we frequently find a 200 pf capacitor on the plate of the 2nd detector. In spite of their high coefficient, these fail surprisingly often. Why?
Someone knowledgeable once suggested to me that this failure is because the Bakelite casing shrinks over time, causing pressure on the elements within. Another possible cause is that some sort of chemical change that seems to affect some RF coils over time increases their Q (Quality Factor). In any case, mica capacitors used in high stress locations like the ones mentioned above are worth testing, as they may actually function as resistors today, not capacitors. These conditions also affect the molded, tubular, Bakelite capacitors we find in late '40s and '50s radios, the ones with the colorful stripes.
Incidentally, I was surprised once when rebuilding a Scott chassis to find flat molded 0.05 paper capacitors that looked like micas. They too showed abnormal leakage.
A voltage check can reveal a host of interesting things about a capacitor. Lifting the cold end of a coupling or bypass capacitor that has B+ voltage on the other end, and taking a reading to ground on the cold end may surprise you, just when you thought that mica was reliable.
--Richard Foster, Cochituate, MA
While mica capacitors are relatively reliable, I replaced several which had caused problems in a Du Mont RA-102 television -- low and missing plate voltages and sweep frequency drift. I can only speculate about bad batches of capacitors and how contaminants get in.
--Ted Hutson, Beverly, MA
A.R.C. -- Fantastic and a Joy
I just wanted to tell you that you have a fantastic publication -- well worth what I pay for it, even though my slumping Canadian dollars are making it more expensive!
--Rob Prince, Toronto, Ontario, Canada
First, let me tell you how wonderful it has been to receive A.R.C. I have fooled around with radio since about 1968, and this magazine has been a joy and help.
--Charles Callahan, Baltimore, MD
Since our mail bag usually includes one or more kudos, we decided to print several in this, the first issue of the new year. (Editor)