Orion AR201

1955

Condition and performance:

	Cabinet:	50%
	Reception AM:	70%
	Sound Quality AM:	70%
	Sound Quality P.U.:	60%

Features:

	P.U. Entrance:	Yes
	Tape Recorder Entrance:	No
	Extra Loudspeaker Output:	Yes, 5 Ohms
	Loudness:	No
	Treble Control:	No
	Bass Control:	No
	Tone Register Switches:	No
	AM Bandwidth Switch or Control:	No
	Tuning Indicator:	No
	Build-in Antenna:	No
	Build in Ferrite or Window Antenna:	No
	Separate AM/FM tuning:	No

Technical Specifications (Partially measured):

	Tubes:	ECH81, EBF80, EL84, EZ80
	Wave Bands:	LW, MW
	Intermediate Frequencies (IF):	473.6 kHz
	Loudspeaker:	Oval, 12.5 x 17.5 cm (Not original)
	Resonance Frequency Fs:	?
	Frequency Range Power Amplifier:	?
	RMS Output Power at 5 Ohms:	2 Watts
	Cabinet:	Wood, brown lacquered
	Dimensions:	38 x 28.5 x 18.5 cm
	Mains Power Voltages:	110, 127, 150, 220, 240 Volts~
	Mains Power Consumption	?
	Retail Price	?

Description:

The Orion AR201 is from Hungarian origin. The tube are made by Tungsram and are still original and in good condition.
If you look at the tube line up, it seems a pre-amplifier tube is missing, but that isn't the case. Usually the ECH81 uses the triode for the AM oscillator, In this case the ECH81 will be used as a screen oscillator. The triode section of the ECH81 is then left over as an audio pre-amplifier stage. This technique makes this radio the a bit special, compared with the usual super heterodyne AM radio's.

Another parts are, when you connect a record player, the audio signal of the AM recption will be switched of automatically
When you connect an external loudspeaker, the inter loudspeaker will also switched off automatically.

Repairs:

First of all I have removed the inside dust of the radio with the air compressor. Taking out the chassis is easy, so the radio is still complete with even the loudspeaker baffle still fitted.
To check the power capacitor, I have taken out all the tubes except the EZ80 and connected the radio to the mains voltage with a series bulb of 220V 60 Watts. Soon I find out the power capacitor has no leakage, but the grid voltage on the EL84 is too high, should be 0 Volts. After replacing the coupling of 10 nF 630V, I can place back the remaining tubes and directly connect to the mains power. The reception of the radio stations is very weak.

The loudspeaker is original and has a diameter of 17.5 cm. The original loudspeaker should have a diameter of 12.5 cm. This loudspeaker obstructs also the dial cord and needle as well as the lack of space for the dial scale lamps.

Here you see the dial cord is missing.

Working on this radio is easy, so I make further repairs to make this radio fully operational, optimal electrical safety and optimal performance.

Tuning capacitor is blocked and make also a shortcut.
Solution: Dismantled and cleaned the tuning capacitor. Adjusted the tuning capacitor to turn smoothly as well as preventing the shortcut. The ball bearing is also lubricated with a little amount of machine oil.
Fitted a new dial cord and made a tuning needle of 1.5 mm² copper wire.
Placed an oval Audax loudspeaker of 12,5 x 17,5 cm. Audax loudspeaker are good quality loudspeakers.
Fitted 2 bayonet lamp sockets, taken from a scrap pinball playfield and fitted 2 lamps of 6.3V 250 mA.
All paper and many mica capacitors are replaced. This improved the performance and reception of the broadcast stations a lot.
Cathode decoupling capacitor of 100 µF on the EL84 is replaced by 47 µF 63V.
Reason: little leakage. A lower capacitor value results also in a bit less bass, but prevents also distortion in the bass.
A 100 nF capacitor in the audio feedback circuit is removed.
Reason: Too much increase of the high frequencies at low volume settings, which makes the sound then too thin and sharp.
15K resistor for the AM oscillator is replaces by 15K 2W.
Reason: Increased in value and traces of overheating.
Added a 1K 1W stopper resistor to the grid of the EL84.
Reason: Improved stability of the power amplifier.

Finally the IF section is re-aligned with a Philips GM2882 service oscillator and the HF section is also re-aligned for an optimal reception.
The radio shows now its real capabilities.

Performance after repair:

The new loudspeaker made a big improvement in sound quality.
Because there is no ludness circuit build in, the negative feedback circuit increases the bass frequencies quite a lot, so the sound is more neutral.
The reception of the AM broadcast station is quite well. Since there is no ferrite antenna build in, the best way is to use a magneting loop antenna, but a piece of wire of 2 meters does also a good job.

Home
Back to Picture Gallery 2
Contact Kees van Dijke