End of the 60`s was the time of the first full transistor Mini Tek Scopes
Fast was still a tube Tek, but something up to 5mc was possible.
SONY Tek Type 323, build 1967.
A single Beam portable with recharchable Batteries and a little transformer to load that. 3kg
The little Tek was in the catalog listed to 925 us$ , too much for a radio servive shop. So they are still rare in the market.
Highest quality inside, all is golden, all transistors are in sockets. A 323 use 1,6 Watts from the Battery, so it can work a very long time.
ten years later Tek made the 200 series, very expensive Mini-Tek portables.
221 is a single channel 5MHz
212 is a 2 channels 0,5MHz
The little 213 is a single channel 1MHz and includes a very exactly RMS onscreen multimeter what can read voltage directly from the probe.
Tek 221, 212, 213
There are also: Tek 214, is a 2 channel 0,5 MHz Storage Tek,
and 211, what is a half 212. I do not own the both, still searching to get them
size relations
221 on a 565greetings
Martin