Collins 30K-5 transmitter

Collins 30K-5 transmitter at Musick Point Radio

  • Type: 30K
  • Model: 5
  • Manufacturer: Collins Radio Company of Canada Ltd, Toronto
  • Serial No: 284
  • Output: A1 – 300W, A3 – 250W
  • Frequency range: 2 – 30 Mc/s
  • Antenna connection: Unbalanced
  • Power requirement: 230VAC, 50Hz, single phase, 7.5A
  • Audio input: High Z, xtal or dynamic

The 30K series of transmitters was manufactured by Collins Radio Company after World War Two, and used by NZ Post Office radio stations.

The 30K-5 was a commercial version of the 30K and 30K-1 amateur radio transmitters designed by Warren Bruene of Collins. It uses two 75TH valves to modulate a 4-125 driven by an 807.

Collins designated the 30K-5 as a two-channel “ground transmitter” for air traffic control. It has relay-selectable RF components for two frequencies that can be pre-tuned. The 30K-5 was built at Collins facilities in Cedar Rapids and Toronto.

Audio bandwidth is limited to 3kc, and clipping can be adjusted between 0 and 12 dB to keep peak modulation just under 100 per cent.

Collins 30K5 meters

Collins 30K5 ID plate

This transmitter was purchased by Musick Point Radio Group in 2020 from the estate of Ron Allen ZL1BYW of Otiria, Northland. We are seeking information on the history of this transmitter.

What we know so far:

  • Ron Allen obtained it from Bruce Rowlings ZL1WB of Whangarei (who died 13 June 2015).
  • Before that, it was owned by a radio amateur in Wellington.
Collins 30K5 preparation
Martyn Seay ZL3CK preparing to partially dismantle the 30K-5 in Ron Allen’s garage before transporting it to Auckland
Collins 30K5 loading
Steven Prout ZL2UV of New Plymouth helping to load the 30K-5. (Steven purchased another of Ron’s transmitters, a Marconi 1509.)
30K5 loaded for transport
The 30K-5 loaded onto Martyn’s motorcycle trailer for the trip to Auckland

Read the story of another 30K-5 transmitter, serial number 275, which was sent from New Zealand to a ham in the USA.