- Country
- Germany
- Manufacturer / Brand
- Philips Radios - Deutschland
- Year
- 1931/1932
- Category
- Broadcast Receiver - or past WW2 Tuner
- Radiomuseum.org ID
- 7406
-
- Brand: Deutsche Philips-Ges.
ebay 122394075652, lacunia
ebay 122394075652, lacunia
This model corresponds to the first use of the commercial name "Superinductance" by Philips. It refers to inductors made with specially good materials, resulting in high Q. The Superinductance name continue in use as late as 1936 for TRF sets. This particular model has 3 tuned circuits, the first two are weakly coupled capacitively by a circuit named "Fusspunkt" in German (footpoint), which makes the return to ground of the two inductors of the LC circuits share one capacitor of 20,000 to 50,000 pfd, while the return to ground of the two tuning capacitors goes directly to ground. Sensitivity of the set is high, it tunes on long and medium wave by pulling the tuning knob, on the right of the picture. The left knob is for switch, volume and I believe it used to have a tone control, also activated by pulling on the knob. This radio follows the very first years of Philips radio production and it still has the side knobs. Soon after this model, the company went to front knobs. I do not know whether this particular set was made in Holland or in Germany.
The first tube, after the double tuned input coils was originally an E452T. In this set I have an equivalent Valvo L4111D (partially hidden), followed by a Philips E452T, as the second RF amplifier. The detector is a REN904, equivalent to a Philips E424. The audio preamplifier is again a REN904 and the final output tube is a Valvo L427D, equivalent to a Philips C443. The rectifier is an RGN1064. The speaker in the 730A was of low impedance, perhaps 4 to 8 Ohms, and it used an output transformer. The model 720 used an older type high impedance speaker. The speaker and output transformer in this particular radio are not original.
Click on the schematic thumbnail to request the schematic as a free document.
- Number of Tubes
- 6
- Conflicting model year with tube data.
- The model date contradicts tube dates. [ C453 (1932)]
- Main principle
- TRF without regeneration; 2 AF stage(s)
- Tuned circuits
- 3 AM circuit(s)
- Wave bands
- Broadcast (MW) and Long Wave.
- Power type and voltage
- Alternating Current supply (AC) / 103; 111; 118; 127; 135; 143; 155; 196; 210; 225; 240; 253 Volt
- Loudspeaker
- Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 21 cm = 8.3 inch
- Material
- Wooden case
- from Radiomuseum.org
- Model: 730A - Philips Radios - Deutschland
- Shape
- Tablemodel, high profile (upright - NOT Cathedral nor decorative).
- Notes
Chassis is very similar to the 720A. The schematic (1932) of the Philips 730A shows the tube line up of the later E452T, E452T, E424, E424 and C443 but this is probably not the original tupe line up. Some collectors show even the E443H as output tube. This all functions but is not the authentical tube line up.
Bis zum Abschluss eines Gerätevertrages zwischen Telefunken und Philips (24. November 1931) war es Philips nicht erlaubt Rundfunkgeräte in Deutschland herzustellen. Philips-Geräte die bis dann in Deutschland verkauft wurden, sind in den Niederlanden hergestellt worden. Lorenz hat in diesen Jahren aber einige Philips-Modelle (wie Paladin) ohne Röhren importiert und mit Telefunken-Röhren in Deutschland verkauft.
- Source of data
- Radiokatalog Band 1, Ernst Erb
- Circuit diagram reference
- Lange + FS-Bestückungstabellen
- Other Models
Here you find 2522 models, 2242 with images and 1536 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from Philips Radios - Deutschland
Collections
The model is part of the collections of the following members.