Philips 291U / 15 Radio

[bobhowe]

Hi just bought a Philips 291u / 15 radio as eventually  to do project and it as in very good condition with look like original Phillips Miniwatt valves and dust . There is not a lot of information about this set on google and was it for the European market instead of the UK ? Did Bush and Philips share there designs as the Bush DAC90A ? came out just after the Philips 291U/15 and both are AC/DC sets and  had similar valve line up as Philips had 4 valves UCH42 UAF42 UL41 UY41 and Bush had 5 Valves UCH42 UF41 UBC41 UL41 U41 . One interesting thing is the aerial is externally on the back of the set pictures to follow soon kind regards Bob

[Mike Watterson]

I don't think Philips & Bush shared designs.
They are only similar in being Bakelite and Ux4x series which many models shared in that era. The Philips is a "Short Superhet". Those were at the more budget end as were AC/DC (transformerless for HT, some series live chassis had an auto-transformer for heaters) and Bakelite.

Both those line-ups of valves were widely used in UK and rest of Europe and probably all the European makers made those valves.

The Mullard version is MUS271. Trader sheet 948. Mullard being a Philips subsidiary from 1928.

The Bush DAC90A and more deluxe DAC10 use capacitive tuning. This Philips uses permeability tuning, which was last used commonly in some transistor car radios.

Interesting set. Apart from the permeability tuning the AGC was odd and can't have been very effective as it's only on V2 suppressor grid. However some 1950s battery valve models had no AGC.

[Mike Watterson]

Mullard version £10 10s in No. 1949
Bush DAC90A £12 1s 8d (brown, cream was 15s 1d more) in Feb 1950. It's similar style to 1946 DAC 90 which ran too hot because it was C series 200mA ocatal valves, though also probably mostly Philips (Mullard in UK) designed valves: CCH35, EF39 EBC33 CL33 (like a series version of 6V6) CY31. The Cx3x Series not used in many sets, from 1940 to 1949. Replaced by Ux4x series from 1948. Those in turn by Ux9x noval series in early 1950s.
The US used octal and then 150mA B7G rather than 100 mA series due to lower line voltage. I doubt they used Rimlock at all.

[Geordie McBoyne]

The pictures of the Philips 291U/15. The set is smaller than the DAC90A. In terms of performance there won't a great deal of difference. No doubt the same amount of heat will will be generated in both sets. The Philips cabinet is a more interesting shape, although that is a matter of taste.

Info from the Radiomuseum: https://www.radiomuseum.org/r/philips_29...1_u15.html

Geordie McBoyne.

[Mike Watterson]

I like the Philips style, but that's taste. With one valve less the dropper resistor is dissipating more, but depends on size and placement as to how hot it gets. Horizontal with deflector is good.

I have a DAC90 needing restore (I think asbestos in it), but I like the DAC10 more than DAC90 / DAC90A because it's got a Bakelite back and grill. My DAC10 goes, but unless I generate local MW & LW there won't be much to listen to on it.

[bobhowe]

Hi Mike thanks for reply when you described the Philips tuner been similar to been in car radios it bought back memories of the Japanese Astor series radios that people burnt out by fitting to a positive earth car without changing the 4 pin plug from Negative to Positive earth . Hi David thanks for posting pictures for me and as you say it is a lot smaller than the Bush DAC90A and as you say the cabinet is an interesting shape and it looks better than in in the picture . Will do a temperature check against the Bush DAC90A when its up and running kind regards Bob

[bobhowe]

Hi David just looked on the Radiomuseum link you kindly posted and the Philips set featured on it has had the external Aerial removed from the back and a piece of wire attached poor reception ? kind regards Bob

[bobhowe]

Hi David is kindly going to provide me the circuit diagram and component layout from the Radio Servicing book volume 1 and that will be very helpful kind regards Bob

[Geordie McBoyne]

Hi Bob,
here is the circuit diagram for the Philips 291U. Also, the under chassis layout and component list.

Geordie McBoyne.

[bobhowe]

Hi David thanks for circuit diagram very helpful kind regards Bob