Hi All,

My niece is about to plonk a Philips radioplayer model 05571 on my workbench to repair. Have checked Kevin Chant's site and he has no listing for it.
Anyone here have a circuit at all??

This is a Pic of the makers valve info stamped on the chassis and it has a tuning indicator up on the dial but basically its a 5 valve and looks like dual or tri band but as yet I have not set eyes upon it.
Plus another pic of the dial glass sent to Brad for posting.

(Looks to be a 4 valve job plus rectifier)

Lindsay

Photos uploaded.

It is a model 441A. It has six valves + a magic eye & a R.F. stage. Still interested in taking it on?!!

https://www.radiomuseum.org/r/philips_441a.html

The schematic there is an abridged version from the AORSM.

I have the full service manual which I can make available here if you are interested.

Keep an eye out with the power transformer. I have seen several with a flaky black tar paper from which windings escape out the side. I have a 132L that is one where that has happened.

If you disconnect anything associated with the speaker transformer, its a typical Philips with feed back, invert the phase and most of them will oscillate.

The ECH4G is a rare animal,, ECH34 from memory replaced it.

Transformer is shielded: Best to fit an earth to get rid of the charge that type puts on the chassis

Marc

Marc,

Thanks for the info...a circuit would be brilliant thanks...6 valves in total which includes the tuning indicator.

Apparently the radio was in regular use and then suddenly stopped..hence the bleat for help.

Lindsay

I have a couple of Philips radios with the zigzag lines like yours. I don't know where they were made.

The circuit in AORSM is fairly tatty Radio Museum looks like the better one to download. The resistor on the tuning indicator is rarely good as are the grid resistors on 6V6 and the plate resistors on the first audio; Across the board in all brands they are never to be left unchecked.

It was going until is wasn't, is a very common scenario in a lot of mechanical, & electrical stuff.

I normally start by visually checking it for the obvious. I had one a while back (not the first) where I cannot understand how the owner did not get zapped just unplugging it. Original wedding present cable of the 50's. 1cap had been changed. It was getting Alzheimer's: Started to Hum because it was forgetting the words.

As it was pretty much working that actually saved work. New caps, cable, wire, the normal resistors recalibrate & out.

Best one this past week: Idiot sent to check the Horse Stud electric fences. Cut all the feeders looking for shorts: One right next to a wire he cut. He'd thrown his arms up: Beyond his level of incompetence. With those fences, if you don't get in quick the animals add to the issue.

14hrs, or so later Its going & all but one fault were visually obvious: Never went to Spec savers. One fault was an underground cable that someone had tried to join: that was a re-cable (20m trench).

Hi Monochrome TV,

Have downloaded the Radio Museum circuit OK but it comes with no valve types listed and the RED stamping on the chassis is not very clear.

A couple are easy but the circuit shows 7 valves and on that chassis stamp I can only count 6 valves.

Amongst your documentation on this set do you have a valve line up listing at all??

Lindsay

Valve line up is 6U7G, ECH4G, 6U7G, 6B6G, 6V6G, 5Y3G & there is a valve layout diagram.

I shall endeavour to prepare a pdf of the service manual tonight.

Monochrome TV,

Is that valve line up V1 = 6U7, V2 = ECH4G, V3 6U7, V4= 6B6G.??? ..other 2 and magic eye are obvious. I ask because it seems the niece asked some friend who is a so called electronics whiz and he had ALL the valves out and fixed nothing.
So knows what is now plugged in where!!

Lindsay

Yes that is correct:

V1 - 6U7G, V2 - ECH4G, V3 - 6U7G, V4 - 6B6G, V5 - 6V6G, V6 - 5Y3G, V7 - EM4

Philips 441A Circuit Diagram
Philips 441A Specifications

Fairly standard arrangement.

V1: 6U7 Pentode, RF amp antenna end

V2: ECH4G Pentagrid, Triode Heptode (ECH34) Frequency converter

V3: 6U7 IF RF amp make sure its got a shield.

V4: 6B6G Duo-diode, Hi mu Triode. 2nd Detector 1st AF

V5: 6V6 Beam Power Output Tetrode.

V6: 5Y3 Duo Diode Filament Rectifier,. I Prefer 600V Caps with it & not below 500V

EM4: Tuning Indicator with Triodes ("P" Base) (EM34 Octal base)

Circuitry on socket is often a big clue. Trap: In order to function well, not only should the IF be re-calibrated but all antenna coils have to be on the same frequency, or you will get attenuation.

Take a photo of the top of the set, or draw, the positions of the valves, should you have no layout diagram.

Documents uploaded to Post 11.

Hi Lindsay, your set looked familiar to me.

Back in 16 Jan 2016 in Special Projects I posted an "AM tuner with magic eye and wax caps".

I used a Philips "2532" chassis and re-purposed the bare chassis using the power tranny and tuning gang and dumping the rest.
Basically the chassis is the same thing as yours.
Typical Philips beautifully made with sealed up tuning and IF coils, point to point single strand white "rubber" wire, lots of shielding between stages and so on.
Problem was the white wire insulation had perished cracking off shorting here and there, but worst of all the complex wave change switch was crumbling! Somehow the wafer material used (like bakelite) was disintergrating and the contacts no longer lined up or made contact.
I could have bitten the bullet and rebuilt the wavechange section with a Paton 1960's wafer switch assembly, but then came to my senses and pulled the lot off and did something else with the chassis.

So the only useful thing I can tell you is.

1/ check the power tranny for failing insulation and winding wires hanging out the side!
2/ examine the wave-change switch for failure (gulp!)
3/ check the wiring for crumbling insulation.

If the set has deteriorated like mine it will be a HUGE re build or become a museum non running display.

Fred.

Thanks Fred and others for the info supply.

As yet have not seen the radio arrive but am guessing it soon will as was niece's grandmothers much loved radio and of great sentimental value and been in regular use for ages until it simply stopped.

Will keep you posted on progress etc.

Lindsay