HGLW can supply and fit modern radio control equipment from many manefacturers that will fit in almost any prototype locomotive
Some of the locos that have been through the locomotive works for R/C fitting or battery conversion include: Several Accucraft Baguley Drewrys A brace of Locomotion Railbuses A Roundhouse Billy A John Turner (I think) Hunslet A big big 0-4-0 An Essel Fowler . . . plus many more
A mixture of R/C gear is used
Other older systems worked on include RCS, 27mhz and 40mhz gear.
A manual Roundhouse Billy in the workshops for R/C fitting and a little TLC
A diminutive Fowler fitted with a 2.4ghz radio system