National & International
Radio Society of Great Britain
New Zealand Association of Radio Transmitters
Amateur Radio Relay League
Wireless Institute of Australia

North Yorkshire Clubs
Craven Radio Amateur Group
Ripon & District Amateur Radio Society
Hambleton Amateur Radio Society
Harrogate Ladies' College Amateur Radio Club
Richmond School Amateur Radio Society
Scarborough Amateur Radio Society
Otley Amateur Radio Club
York Radio (Amateur) Club
York Amateur Radio Society

Other
G0KRB's Amateur Radio Links

Local Businesses
Triode Energy Limited
Razorblue Ltd
Electratech (UK) Ltd