Re: Heathkit RF1U Signal Generator Restoration
Waveform:
The RF waveform of the RF1U was checked on several ranges as far as my 20 MHZ Hameg 203-7 analogue scope could cope with, which proved to be a good deal higher than I’d imagined! The 'scope coped well up to 30 MHz, showed a good trace at 55 MHz and even a reduced trace at 88 MHz! Not just a good test for the scope, but for the new pair of e-bay-sourced 100 MHz scope probes at £7.60 the pair post free recently bought from a UK supplier.
The AF waveform was also good, and when used to modulate the RF waveform, the modulated waveform looked good too.
Pic 1: 465kHz unmodulated waveform
Pic 2: 465kHz modulated waveform.
Pic 3: 1 MHz modulated waveform
Pic 4: 30 MHz unmodulated waveform.
Pic 5: Scope trace at 55.5 MHz
The generator had a mixture of odd knobs rather than its original Heathkit knobs, so I bought a set of matching knobs to tidy it up.
Test sockets:
The three sockets (‘AF In, AF Out, RF Out’). are TV connectors known in Europe and Australia, (maybe elsewhere too), as ‘Belling-Lee connectors’, (IEC 61169-2 radio-frequency coaxial connector, type 9,52), whereas for many years, most test gear has featured ‘BNC’ connectors. Arguably the sockets on the RF1U could be replaced with BNCs, but they’re perfectly functional, neat, and original. Given that Belling Lee sockets and plugs are widely used for terrestrial VHF/UHF roof antennas, antenna signal amplifiers, CATV distribution equipment, TV sets and FM / DAB-radio receivers, they’re well up to the task, so I’ve left them in situ.
I hope the write-up might prove useful and of interest.
__________________
David.
BVWS Member.
G-QRP Club member 1339.
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