HRO Prototype
National Company; Cambridge & Malden (MA)
- Country
- United States of America (USA)
- Manufacturer / Brand
- National Company; Cambridge & Malden (MA)
- Year
- 1934/1934
- Category
- Commercial Receiver (may include amateur bands)
- Radiomuseum.org ID
- 86412
-
- alternative name: National Toy Co.
- Brand: Thrillbox
1934 National Catalog No.240
1934 National Catalog No.240
National Catalog No. 240 from 1934
National Catalog No. 240 from 1934
National Catalog No. 240 from 1934
- Number of Tubes
- 9
- Valves / Tubes
- 6D6 or 58 6D6 or 58 6C6 or 57 6C6 or 57 6D6 or 58 6D6 or 58 6B7 or 2B7 42 or 2A5 6C6 or 57
- Main principle
- Superhet with RF-stage; ZF/IF 456 kHz; 2 AF stage(s)
- Tuned circuits
- 11 AM circuit(s)
- Wave bands
- Broadcast plus more than 2 Short Wave bands.
- Power type and voltage
- Powered by external power supply or a main unit. / 115 Volt
- Loudspeaker
- - This model requires external speaker(s).
- Power out
- 1.5 W (unknown quality)
- Material
- Metal case
- from Radiomuseum.org
- Model: HRO [Prototype] - National Company; Cambridge &
- Shape
- Boatanchor (heavy military or commercial set >20 kg).
- Dimensions (WHD)
- 440 x 220 x 300 mm / 17.3 x 8.7 x 11.8 inch
- Notes
-
The National HRO (Prototype) was introduced in National's Catalog No. 240 from October 1934. It has a coverage from 1.7 - 30 MHz in four bands utilizing four ganged coil sets (1.7 - 4; 3.5 - 7.3; 7 - 14.4; and 14 - 30 MHz), which were supplied with the receiver. In addition, two coil sets, covering the broadcast band were available as accessories. Has the then new PW Micrometer Dial and rosette knobs. Receives AM/CW/SSB (BFO).
In Communications Receivers: The Vacuum Tube Era (4th edition), the author writes, "This model shown in advertisements in QST from Oct., 1934, thru Jan., 1935, had no RF Gain, BFO Pitch controls or 'S' meter switch. Round, unskirted knobs. Probably never shipped this model." The author gives no reason for this conclusion. However, this receiver appeared in a two page spread in the No.240 National Catalog from 1934-5.
- Net weight (2.2 lb = 1 kg)
- 14.5 kg / 31 lb 15 oz (31.938 lb)
- Source of data
- Communications Receivers
- Mentioned in
- National Catalog No. 240 - 1934
- Author
- Model page created by Martin Bösch. See "Data change" for further contributors.
- Other Models
-
Here you find 445 models, 284 with images and 189 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from National Company; Cambridge & Malden (MA)
Collections
The model is part of the collections of the following members.