Eddystone EC10 Mk.II. Vintage: 1967-1977.

Main spec. as EC10 Mk.I (q.v.), but Mk.II features additional fine tuning knob, S-meter and a stand-by switch.

► Collector's notes.
One of Eddystone's most successful selling receivers aimed at the Amateur Radio / SWL market. As such, they are remarkably common. Nevertheless, over the period Dec. 2009 - Dec. 2011, this receiver is still in great demand on the S/H market, where it fetches a good price. It has a very distinctive appearance which makes it instantly recognisable.

--------------------------------------------------------------------------------
Photo. & comment submitted by Al.(Skywave): Dec. 15, 2011.

Hallicrafters Super Skyrider SX17, this receiver predates the Super Skyrider SX28. A 13 valve single conversion superhet covering 545 Kc/s to 62 Mc/s in six bands with an IF of 465 Kc/s, the receivers BFO has a user injection amplitude control as well as the usual BFO frequency control.
Also incorporated is a single pole Xtal filter and provision for switching in two IF bandwidths as well as switchable automatic noise limiter of the single diode variety. The main tuning dial incorporates a vernier scale and automatic band pointer, the bandspread logging dial is a rather quirky spiral scale with an illumination window that mechanically tracks the dial reading when tuning, the scale is numbered 0 to 1,000 an "S" meter is also fitted as standard.
This particular receiver is the dual AC voltage version, I think this receiver is generaly underated considering the age of the design, at first glance the logging scale and drive look pretty basic but it will tune just over 900 Kc/s from end to end on the 20 meter band with thirty or so turns of the control ie 30 Kc/s per full revolution which matches or betters that found on the HRO on that band.
Tuning CW bang on the Xtals nose is no problem, the drive when properly serviced and adjusted has zero backlash and is silky smooth.
As with a lot of the Hallicrafters, it has plenty of audio via two 6V6's in push pull, the 6V6's being driven via a phase splitter transformer, it claims to push out 13 watts class A before drawing grid current!
The SX17 is an easy rig to work on compared to some, with plenty of room underneath to manouver. The IF transformers are iron cored but the tuning of them is via air spaced variable capacitors.
The receiver shown is all workie workie and runs on 95% of its original components, however because of the make and type of components fitted my experience tells me that I should do a systematic replacement at some point.
Out of my limited collection this is my second favourite receiver of that era next to the HRO.
In the picture there is a partial glimps of the speaker that came with it, it is not the usuall Hallicrafters type, I have heard from someone in the States who has one of these speakers and he told me that it was supplied for one of the Sears range of receivers that was a re badged Howard Radio model, Howard Radio appear to have a had working relationship with Hallicrafters in the early days so far as I can ascertain, wether the speaker shown was supplied originally I can't say with any certainty.

Lawrence 15/12/2011.

Eddystone: model 990R. Vintage: late 1960's → early 1980's.

Photo. shows an early production item; later models have a much lighter colour front panel.
Single conv. s/het., 27 - 240 MHz in 4 bands. AM/CW/FM. I.F. 10.7 MHz. User-selectable I.F. B/W: 30 kHz / 200 kHz.
Can accommodate crystal-control for the L.O. for fixed channel use.

Was a popular choice for monitoring purposes by Civil Authorities. It is also useful as an item of 'test equipment' for checking for spurious & harmonic signals from 'home-brew' transmitters and such like! (Speaks from experience! :cool:)

--------------------------------------------------------------------------------
Photo. and comment submitted by Al. (Skywave): Dec. 15, 2011

Eddystone EC10 Mk.1 (Early version). Vintage: early-mid. 1960's.

Gen. coverage comms. receiver, AM/CW, 550 kc/s - 30 Mc/s in 5 bands.
Internal battery or external a.c. mains unit. Integral speaker.
Single conv. s/het., 1 RF stage, 465 kc/s I.F.; uses germanium transistors.

The above design inevitably means that the image rejection ratio (IRR) will be poor above approx. 14 MHz. The build quality inside is somewhat less than what those who are familiar with the inner construction of Eddystone radios have come to expect. Nevertheless, it is a popular Eddystone model amongst collectors.

► Maintenance note.
Uses germanium transistors: the types that grow 'whiskers'. Maintenance is awkward since access to the main pcb inside is difficult.

A rare variant of the Mk.II is the Mk.II/S. This features an integral FM stereo decoder for connection to an external hi-fi system. The front panel appearance of either is identical: look around the back!

Al. / Dec. 13, 2011 //