[turretslug]

^Wot they say^! Potentially, it's an excellent radio- it follows the relatively conventional and established architecture of the likes of HRO, CR100, AR88 etc, but in an era when the market was awash with high-performance comms-orientated receivers from WW2, the BRT400 tried a bit harder with circuit detail, particularly as regards AGC performance, low-distortion detection and good audio fidelity. Unfortunately, the design crams rather more componentry than an AR88 into a shorter chassis and it must be one of the most challenging sets to work on. To compound the problem, with the CR100 and the AR88, the RF section can be removed from the main chassis as a "sled" for easier overhaul but the BRT400 has all the RF section screening seam-soldered to the main chassis making this part of the set something of an access nightmare. Not impossible, just very difficult and trying!

Further more, there's a lot of power consumed- a similar number of valves to an AR88 take about twice the HT power. The signal valves represent an early approach to low-noise performance, taking quite high anode current, the AF output is a beefy KT81 with nearly an amp of heater current and, as if that wasn't enough, another KT81 provides active smoothing. All that makes for a whopping mains transformer, hemmed in on the busy chassis with a gently-charring choke barbecueing it from underneath and a couple of big tubular wire-wounds roasting the terminal panel on top. Check the loom here carefully, the insulation chars and crumbles and as it carries mains and HT AC, it's no trifling problem.

It's a shame that they didn't relent to a chassis a few inches deeper, more like the AR88. It does have a certain "post-war kitchen appliance" charm with its chroming and pastel colours, at least compared to many dour and utilitarian comms receivers.

TBH, not for the faint-hearted, though an aspiring key-hole surgeon might relish it!