Marconiphone model 4181 Long, medium wave and VHF portable transistor radio housed in plastic case with carrying handle. The same radio was also made under the HMV and Ferguson brand names as model 2181 and 3181 and possibly Ultra 6181. Mains battery versions were available (4182 and 2182 respectively). It uses four 1.5 Volt D cells. All these models which were essentially the same internally incorporated 7 transistors and an audio amplifier integrated circuit. British Radio Corporation [part of Thorn Group] made in UK 1973/4
The back cover which incorporates the six cells and sockets for aerial, external 9 Volt supply, tape socket and earphone jack.
When I received the radio it was not
working and had been sitting on a shelf for more than a year before I
decided to clean it up and find out why it was so silent. This was soon
solved, the contact in the external power supply socket was not making
good connection. I also noted that one of the battery connection
springs was corroded and the pointer behind the dial was not visible
though I was able to tune into station on all three wavebands. When I
removed the rod aerial and the 5 screws holding the aluminium strip
(shown in the image above) the orange pointer could be seen lodged at
one end of the scale caught by a warped piece of black PVC tape which
when removed would allow free movement of the pointer along the track
behind the dial. I set in in position for the BBC long wave
198 kHz put it all back together cleaned the battery connections and
the radio now works as well as perhaps it did 40 years ago, though not
in the pristine condition it once was.
This is one of a number of radios which belonged to the late Ron Griffiths which were given to me by his widow in 2013. Ron was was an engineer, working for himself and making parts for other firms. He made some items for the Pastorelli firm - brass cases for surveying equipment that is used in tropical climates - and also brass parts for Cambridge Instruments.