Here's the marketing information:
Single Band, CW Transceivers
DTR 3-5 (3.5 / 3.6MHz) DTR7-5 (7.0 / 7.1MHz) DTR10-5 (10.1 / 10.2MHz)
These little rigs can produce any output power from less than 25mW to around 8W. They all have a very effective 7 pole low-pass filter resulting in a harmonic level of better than 50dB below the main output.
The receiver incremental tune (RIT) allows about +/- 4kHz of fine tuning around the transmitter. And the stable VFO is controlled by the new Jackson calibrated ball-drive - well known for its clean appearance and smoothness of operation.
Receiver (DC) sensitivity is better than 1microV minimum discernable signal (MDS) and selectivity, with the included audio filter, is around 250Hz @ 6dB. A 12 dB (switchable) attenuator deals with any high-powered AM breakthrough.
Power requirements : 12/14Vdc,
1A (key down) at 5W output.
Postage (UK) £4.00
TU4 Antenna Tuning Unit
Very similar in style to the DTR series of transceivers, the TU4 is conservatively rated at 80W and covers the HF spectrum.
Based on the well proven "L-Match" circuitry, the TU4 can be configured into any of three different arrangements, making it easy to obtain a match with a wide variety of transmitter/band/antenna combinations.
The LAKE "PLANAR" inductor is a feature of the unit. PCB based, the coil is of flat rectangular form rather than the traditional helix. There are several advantages to this system - the unloaded "Q" is around 60, measured at 5MHz, self capacitance is low, about 5pF, and tappings are easily arranged in exponential increments of inductance.
The tuning capacitor is a high grade air-spaced unit made by Jackson.
The built-in SWR meter is exceptionally sensitive. Based on the 'Bruene' bridge circuit, less than half a watt is sufficient to give full scale deflection of the meter at 3.5MHz. Ideal for QRP operation!
Frequency range : 1.5 - 30MHz
- Power rating : 80 watts (CW) Includes 4:1 Balun for balanced
Postage : (U.K.) £4.00
Another British piece of amateur radio gear, this time based on valves rather than transistors.. This "transverter" represented a cheap way of getting onto 2 meters as it merely upconverted the 10 metre range of a standard HF transceiver to that VHF band. Admittedly one had to provide a power supply and hide it away under the bench, but, overall it cost a lot less than an equivalent Japanese black box and provided increased output power over the latter, with its Mullard QQV03-20A output valve.
As they used to say. "Why not make use of the high specifiction of that really expensive HF transceiver on two meters?"
Although a good idea they didn't really catch on because the new Japanese stuff looked so good, and despite their astronomic prices and disgraceful "price fixing", reminiscent of the goings on in the British radio industry of yesteryear, sold well.