Gerard's Tokyo

179
Item nr.

Tokyo Portable

Cheap and simple job, but doesn't look too horrible.

**Data for Tokyo**
Production	Japan, 1974.
Bands	MW (540-1620 kHz).
Semi- conductors	2SA15 (osc/mix), 2x2SA12 (IF), 2SB75 (driver), 4x 2SB77 (output).
Cabinet	Cardboard. Size 19x12x6 cm. Weight 525 gr.
Power	Batt 4xAA.

The Design

The little brother of the Tokyo Super, which has 10 transistors and two bands (LW as well).

The frequencies are considerably more cramped on the high end of the scale than on the low end. As the photo of the dial shows, halfway the scale (at index 5) we are at about 740 kHz. This means that there is about 200 kHz (or 22 channels) on the left half, and 980 (110 channels) on the right half of the dial scale. This phenomena is a consequence of how capacitor capacity relates to frequency, but many radios have at least some trick built in to reduce the effect a little.

Obtained	4/2001 from Rommelmarkt Bergwegkerk.
Condition	9.
Disposed	Sold 12/2004.
Sound sample	PLAY SOUND Following a request of AudioEase we have made recordings of test sounds played in some of our tube radios. The goal is to produce software that will mimic the typical sound of a tube radio. You hear the test recording of the Tokyo; read more about this project in my FotoAlbum.

This Object

Here is the usual inside photo. Observe half of the transistors (the four outputs) are cramped on a square centimeter of the print board. The output stage is a push-pull, with 2 of the 2SB77 transistors in parallel at each end.

At first the radio didn't work but this turned out to be just some dust in the on/off switch.

Part of Gerard's Radio Corner.
Generated by SiteBuilder on 26/2/2024 by Gerard (g.tel@uu.nl)