Plenty of stuff on the HRO on the web, they come up often on Ebay, unless it's a real dog that's been got at they tend to go between £100-£150 (ish)
The most common ones (on Ebay at least) are the MX variant and the 5t variant, both table models.
The HRO MX does not have a plug in xtal for the xtal filter like the HRO Senior did, it's hard wired inside the phasing control box, the MX still used 6 pin valves (UX6 base) the same as the original HRO Senior did.
The HRO 5t has the same xtal arrangement as the HRO MX but the valves used are different, they are metal enveloped with an octal base, the sound output valve however is still a glass envelope job.
Most if not all of the HRO 5t's appear to have been manufactured during 1945, most were tropicalised.
I've enclosed a picture of a couple I have, the one in the foreground is the HRO 5t, it has an R106 MK11 badge on it as well (a military designation) the one in the background to the right is the HRO Senior, that particular one is a rack mounted version, the front control panel of that is 5 mm aluminium, the case and panel on the HRO 5t is all steel.
Band changing is by plug in coil packs which are inserted/removed from the front panel.
Electronically and mechanically they are very simple and elegant and are very good performers when set up and working correctly plus they are not heavy..
The PW tuning drive needs no explanation it's a bit of a legend.
Lawrence.
The most common ones (on Ebay at least) are the MX variant and the 5t variant, both table models.
The HRO MX does not have a plug in xtal for the xtal filter like the HRO Senior did, it's hard wired inside the phasing control box, the MX still used 6 pin valves (UX6 base) the same as the original HRO Senior did.
The HRO 5t has the same xtal arrangement as the HRO MX but the valves used are different, they are metal enveloped with an octal base, the sound output valve however is still a glass envelope job.
Most if not all of the HRO 5t's appear to have been manufactured during 1945, most were tropicalised.
I've enclosed a picture of a couple I have, the one in the foreground is the HRO 5t, it has an R106 MK11 badge on it as well (a military designation) the one in the background to the right is the HRO Senior, that particular one is a rack mounted version, the front control panel of that is 5 mm aluminium, the case and panel on the HRO 5t is all steel.
Band changing is by plug in coil packs which are inserted/removed from the front panel.
Electronically and mechanically they are very simple and elegant and are very good performers when set up and working correctly plus they are not heavy..
The PW tuning drive needs no explanation it's a bit of a legend.Lawrence.
