Radios before this year provided the old (Armstrong) band, and just the following year Zenith dropped the old band and made the 7H820U and 7H820-Z with just the one new (RCA) FM band. This radio uses the "Armstrong System" for FM tuning, indicated by the label on the radio's back. RCA continued to hound Armstrong and won the patents on FM as well, arguably leading to Armstrong's suicide in 1954 from endless litigation and Armstrong's financial ruin. Truth being stranger than fiction, Armstrong had once worked for RCA and in 1923 had married the secretary of RCA President David Sarnoff (Sarnoff being later responsible for the war against FM and Armstrong).
After his suicide Sarnoff reportedly stated, I did not kill Armstrong. This radio is also the first Zenith to place the tone control in the center of the speaker cone, labeled "Tone Register" in the photos.
This continued in many future Zenith models. Tuning the tone control at the center of the speaker gives the illusion of "tuning" the speaker itself.This model also uses the newly introduced miniature tubes (7 in total) and a solid-state selenium rectifier. This is a larger table radio, about 15" W x 8" D x 9 H, and weighs 12 lbs (unpacked). If you want to add an external antenna or length of wire. The back cover has an interlocking power connector to prevent the shock hazard of opening the case with the power cord plugged in. The left knobs are bandswitch and tuning, the center knob is the continuous tone control, and the right knob is the off-on-volume control. While this is not a restored radio I did fix a couple of things. One of the two dial cords was broken, so that is fixed and the knob now tunes the radio and turns the dial pointer. I tested all 7 tubes and replaced 5 that were weak or questionable with new old stock tubes (12AU6, 19T8, and three 12BA6). All tubes read good now on my mutual transconductance tube tester. Be sure to look at all the photos to assess condition. I shot the cabinet with and without flash to show the bakelite under different lighting. The bakelite has some blemishes but looks nice in my opinion, and it has no cracks. Working 1948 Zenith 7H820 Bakelite AM/FM 3-band radio Armstrong System" is in sale since Wednesday, February 03, 2016. This item is in the category "Collectibles\Radio, Phonograph, TV, Phone\Radios\Tube Radios\1930-49". The seller is "g-books_com" and is located in Pacifica, California.
This item can be shipped to United States, to Canada, to United Kingdom, DK, RO, SK, BG, CZ, FI, HU, LV, LT, MT, EE, to Australia, GR, PT, CY, SI, to Japan, to China, SE, KR, to Taiwan, TH, to Belgium, to France, to Hong Kong, to Ireland, to Netherlands, PL, to Spain, to Italy, to Germany, to Austria, RU, IL, to Mexico, to New Zealand, SG, to Switzerland, NO, SA, AE, QA, KW, BH, HR.