Radio Broadcast (May 1928-Apr 1929)

52 RADIO BROADCAST ADVERTISER Model 528 Three Ranges 1 50/8/4 Volts for Testing A. C. Receivers For checking up supply and t ube voltages — ■ a small, compact and portable instrument of highest quality and electrical performance, yet moderate in price. Open scales, responsive and excellently damped. At all dealers or write to : — WESTON ELECTRICAL INSTRUMENT CORP. 604 Frelinghuysen Ave. Newark, N. J. WESTON RADIO INSTRUMENTS Jenkins & Adair Condenser Transmitter For Broadcasting, Phonograph Recording, and Power Speaking Systems THIS transmitter is a small condenser which varies its capacity at voice frequency, and is coupled direct into a single stage of amplification, contained in the cast aluminum case. The output, reduced to 200 ohms, couples to the usual input amplifier. The complete transmitter may be mounted on the regulation microphone stand. It operates on 180 v. B and 6 or 12 v. A battery. This transmitter contains no carbon, and is entirely free from background noise. Its yearly upkeep is practically nothing. It is extremely rugged, and will withstand hard usage. Price, complete with 20 ft. shielded cable, $225.00 F.O.B. Chicago. J. E. JENKINS & S. E. ADAIR, Engineers 1500 N. Dearborn Parkway, Chicago, U. S. A. Send for our bulletins on Broadcasting Equipment /TlHE list below has just been released by the Navy Department, radio service, to Radio Broadcast. It includes the press, weather hydrographic, and time signals transmitted by United States Naval Stations throughout the world. This list supersedes that appearing on page 514 of this magazine for March, 1927. The material in columns three and four below is of especial interest. The abbreviations employed and their meaning follows: "i.c.w." interrupted continuous wave; "c.w.," continuous wave; "a.c.w.," raw a.c. These trans missions are of vital importance to all marine and shore station operators. Other readers who are interested in listening to these signals should employ a simple regenerative circuit with a long antenna. A satisfactory receiver for this purpose wa$ described on Radio Broadcast Laboratory Information Sheet No. 19, August 1926. Also, the article, "A Portable LongWave Receiver," page 166, Radio Broadcast, July 1927, describes a receiver especially designed for long-wave reception. Time (Greenwich Civil) Station Call Sign Frequency in kc/s and Type of Emission Material Broadcast 0000 Brownsville, Tex. NAY 132 i. c. w. Weather. 0045 San Juan, P. R. NAU 48 c.w. Weather (1 July to 15 November). 0100 Norfolk, Va. Puget Sound, Wash. NAM NPC 122 i.c.w. 118 c.w. Weather Weather. 0115 Arlington, Va. NAA 4015 i.c.w. Aviation iceather and upper air reports. 0130 Eureka, Calif. Norfolk, Va. NPW NAM 104 i.c.w. 122 i.c.w. Weather, hydrographic. Weather. 0200 Cavite, P. I. Guantanamo Bay, Cuba. San Juan, P. R. NPO NAW NAU 56 c.w. & 112 i.c.w. 118 i.c.w. 106 i.c.w. Press. Weather (1 June to 15 November). Weather (1 July to 15 November). 0255 to 0300 Arlington, Va. Annapolis, Md. ^aviie, i . l. NAA NSS NPO 112 i.c.w. 690 i.c.w. 4015 i.c.w. 8030 i.c.w. 12045 Law. 17.6 aw. 56 c.w. 112 i.c.w. Time Signals. Time Signals. T ime Signals. 0300 Arlington, Va. Cavite, P. I. Key West, Fla. Puget Sound, Wash. NAA NPO NAR NPC 36 c.w. 112 i.c.w. 56 c.w. 112 i.c.w. 102 i.c.w. 118 c.w. Marine Weather folloiced by Navigational Warnings and ice reports (in season) . Weather, hydrographic. Weather, hydrographic . Hydrographic. 0305 Navy Yard, Wash. D. C. NAA 690 voice Weather. 0330 San Francisco, Calif. Tutuila, Samoa NPG NPU 42.8 c.w. 108 i.c.w. 66 c.w. Weather, hydrographic. Hydrographic. 0355 to 0400 Balboa, C. Z. Colon, C. Z. NBA NAX 46 c.w. 132 i.c.w. Time Signals. Time Signals. 0400 Arlington, Va. Great Lakes, III. Puget Sound, Wash. San Juan, P. R. NAA NAJ NPC NAU 4015 i.c.w. 132 i.c.w. 118 c.w. 48 c.w. Weather broadcast to Europe. Weather, hydrographic. Weather. H eather. 0430 Astoria, Oreg. San Diego, Calif. NPE NPL 112 i.c.w. 102 i.c.w. Hydrographic. Weather. 0500 Brownsville, Tex. NAY 132 i.c.w. Weather. 0555 to 0600 San Francisco, Calif. NPG 42.8 c.w. 62 c.w. 108 i.c.w. Time Signals. 0600 San Francisco, Calif. NPG 108 i.c.w. Weather, hydrographic. 0630 Honolulu, T. H. NPM 54 a.c.w. Weather, hydrographic. 0700 Annapolis, Md. Arlington, Va. NSS NAA 17.6 c.w. 112 i.c.w. Press. Press. 0730 Tutuila, Samoa NPU 66 c.w. Hydrographic. 1000 Balboa, C. Z. Balboa, C. Z. Colon, C. Z. San Diego, Calif. NBA NBA NAX NPL 46 c.w. 118 c.w. 132 i.c.w. 30.6 c.w. Press and hydrographic. Press. Hydrographic. Press. 1300 Puget Sound, Wash. NPC 118 c.w. Weather. 1315 Arlington, Va. NAA 4015 i.c.w. 8030 i.c.w. 12045 i.c.w. Aviation weather and upper air reports. 1330 Norfolk, Va. NAM 122 i.c.w. Weather. 1355 to 1400 Cavite, P. I. NPO 56 c.w. 112 i.c.w. Time Signals. 1400 Cavite, P. I. NPO 56 c.w. 112 i.c.w. Weather, hydrographic. 1500 Arlington, Va. NAA 112 i.c.w. 16060 Law. Marine weather followea by ice reports (in season) . 1505 Arlington, Va. NAA 690 voice W eather.