HAM Radio

[Lionelgee]

Hello AULRO people,

I would like to get a better clarification on what techniques used to be used on the old dial operated HAM radios. I would like to be able accurately describe the tuning in process. I want to put this description into explain part of my research.

From my one distant memory of a HAM radio it had a number of hand operated dials which graduated in size from the first dial being the largest down to smaller dials.

I think the first and largest dial was a coarse tuning which was used to locate signals in between the static. Once a suitable blip was located the other dials were used to fine tune on to the first signal located by the first and largest dial.

Each smaller dial worked within smaller wavelengths until the radio had reached its finest adjustment and the clearest signal. The HAM Radio operator would then log these frequency settings into a diary.

Can someone please correct any mistakes I have made in the summary of the use of the different dials and provide me with the correct terminology?

I hope I have not upset any HAM radio enthusiasts with my ignorance towards your topic of interest!

Your assistance will be most greatly appreciated.

Kind Regards
Lionel

[LowRanger]

Lionel

Depending on the brand of the transceiver,they are all slightly different.Also depending on if the transceiver is full valve or a hybrid or full solid state,they are all different.Also are you after tuning of the reciever only,as the transmit requires its own tuning proceedures.

[rover-56]

Hi Lionel,

Not that familiar with the older amateur radios, but I think what you are remembering is that there would be a BAND dial to set the band wanted (eg 7.0MHz, 14MHz, etc.) usually a rotary switch selecting tuning coils.
Then there would be a 'bandspread' dial which would allow tuning across the band chosen (eg 7.00MHz to 7.3MHz).
Then there may be a 'clarifier' knob which is a very fine tune control used to zero in on the frequency to give clear reception of SSB transmissions.

Hope that helps:)

Cheers,
Terry
vk3kda

[LowRanger]

Hi Lionel,

Not that familiar with the older amateur radios, but I think what you are remembering is that there would be a BAND dial to set the band wanted (eg 7.0MHz, 14MHz, etc.) usually a rotary switch selecting tuning coils.
Then there would be a 'bandspread' dial which would allow tuning across the band chosen (eg 7.00MHz to 7.3MHz).
Then there may be a 'clarifier' knob which is a very fine tune control used to zero in on the frequency to give clear reception of SSB transmissions.

Hope that helps:)

Cheers,
Terry
vk3kda

The "bandspread" dial,is commonly called the tuning dial,but is usually known as the VFO.
The "band" dial can also be known as the "preselect" dial.
You may also have a "loading" knob,which even for just receive,is adjusted to align the Pi network,to match the feedline and antenna impedence.Which you would set on recieve for maximum noise.
The other thing that you often hear in movies,is the high pitched "Tone" as someone is moving the VFO looking for someone on the old radio.Normally you would have a tuning preselect frequency at 25Khz and 100Khz spacing.You would then turn the main tuning knob (VFO) to the closest desired marker frequency,and turn the "preselect" knob for maximum "S" meter deflection and then tune the VFO for the 100Khz tuning signal and Zero beat.What this means is that the 100Khz signal is a tone either side of the carrier signal and you tune until both tones merge.
This is a very simplistic overlay of setting the initial receive stage of the radio

[Lionelgee]

Lionel

Depending on the brand of the transceiver,they are all slightly different.Also depending on if the transceiver is full valve or a hybrid or full solid state,they are all different.Also are you after tuning of the reciever only,as the transmit requires its own tuning proceedures.

G'day Low Ranger,

Thank you for the reply. It was decades ago since I saw a radio like the one I can remember. I am more interested in getting the tuning described for recognising incoming signals.

Kind Regards
Lionel

[Lionelgee]

Hi Lionel,

Not that familiar with the older amateur radios, but I think what you are remembering is that there would be a BAND dial to set the band wanted (eg 7.0MHz, 14MHz, etc.) usually a rotary switch selecting tuning coils.
Then there would be a 'bandspread' dial which would allow tuning across the band chosen (eg 7.00MHz to 7.3MHz).
Then there may be a 'clarifier' knob which is a very fine tune control used to zero in on the frequency to give clear reception of SSB transmissions.

Hope that helps:)

Cheers,
Terry
vk3kda

G'day Terry,

Yes I can remember at least three dials and I think I recall the operator going from the biggest dial and then honing in on the signal by using each of the smaller dials. I cannot recall if these smaller dials were also graduated in size too.

Kind Regards
Lionel

[Lionelgee]

The "bandspread" dial,is commonly called the tuning dial,but is usually known as the VFO.
The "band" dial can also be known as the "preselect" dial.
You may also have a "loading" knob,which even for just receive,is adjusted to align the Pi network,to match the feedline and antenna impedence.Which you would set on recieve for maximum noise.
The other thing that you often hear in movies,is the high pitched "Tone" as someone is moving the VFO looking for someone on the old radio.Normally you would have a tuning preselect frequency at 25Khz and 100Khz spacing.You would then turn the main tuning knob (VFO) to the closest desired marker frequency,and turn the "preselect" knob for maximum "S" meter deflection and then tune the VFO for the 100Khz tuning signal and Zero beat.What this means is that the 100Khz signal is a tone either side of the carrier signal and you tune until both tones merge.
This is a very simplistic overlay of setting the initial receive stage of the radio


Hello Again Low Ranger,

Simplistic is good :D. Now you mentioned the VFO - what does VFO stand for?

Kind Regards
Lionel

[Lionelgee]

Hello All,

I found an image of what I think was something close to what I remember seeing years ago. One big main dial with at least two other smaller dials and some switches and a rotating frequency face in a part circle display. Also a gauge with a needle measuring something?

The radio set I can remember had a much bigger main dial than the one shown - it was nearly a hand span in diameter. Otherwise the image below is very close to what I remembered.

Okay the description does mention that the radio is 30 years old and I thought that was rather an unkind thing to say; because it certainly dates me too!

Accessed 5/06/2013 from Coastal NC Fishing - Information on great Fishing and Amateur Radio KJ4FKC (http://coastalncfishing.com/page/2/)

Kind Regards
Lionel

[LowRanger]

Lionel
VFO stands for Variable Frequency Oscilator.

The Picture you posted is of a Yaesu Ft101E,which was the last of the non digital display 101 series HF radios.If you have a look at the the dials/knobs on the radio in picture,you will see all the ones I mentioned.
As far as the size of the dial is concerned,this may have been an ex military unit that you are talking about.As I have owned valve radios by most of great manufacturers,such as Collins,Swann Yaesu and Kenwood as well as the solid state and hy-brid units from these manufacturers and more,and they are all fairly similar in size.
As far as tuning in to actually just listen,then after the radio is initially set up,you can just turn the VFO (main tuning dial) until you hear someone,then if you are on sideband ie LSB or USB then you can use the clarifier to andjust the sound so that you can understand it at a pitch that suits your ears.

[Lionelgee]

Hello All,

Is there still the requirement in Australia for ham radio operators to be proficient in Morse Code before they can get their licence?

Kind Regards
Lionel

[wrinklearthur]

Hello All,

Is there still the requirement in Australia for ham radio operators to be proficient in Morse Code before they can get their licence?

Kind Regards
Lionel

No ! :)

vk7kba

[Kevin B]

Have a Look here, it Relates to Kenwood Hybrids, but its the basic Concept for most Valve Driven Radios,

Kenwood Hybrid Tune-up Procedure (http://www.k4eaa.com/tune-upP.htm)

Regards
Kevin
Vk2erp

[dromader driver]

Aaaah Eddystone

Was using a 6mhz network whilst working in PNG and the aircraft were on it all the time and generally reliable. :cool: