What are those buttons for

A modern HF radio is a marvel of technology. But often they are so complex that a lot of the controls never get touched! Or if they do, people are unsure what exactly they do and use them incorrectly.

So let’s look at some of the functions on a modern HF radio and how you can use them.

Anyone coming from a CB background will be pretty familiar with the squelch control. It basically turns off the audio on the radio until a strong enough signal opens it. Squelch can be very useful (if not essential) as the continuous hiss of a blank FM channel can be very annoying.

Squelch is used somewhat less on SSB as the background noise is generally quieter, but there is no reason why you couldn’t use it. If you are monitoring a specific frequency on your radio for hours on end it can be useful to squelch the audio on SSB to help retain your sanity!

Noise Reduction

The HF bands can be quite noisy at times and digital noise reduction can be a way of making the audio easier on the ears. The best approach is to engage the noise reduction button and then advance the noise reduction gain knob until you get the effect you are looking for. If you advance it too far the chances are that you will end up with very muddy audio, sounding like someone has their head in a bucket!

Notch/Auto Notch

If you have a whistle or tone on your received signal a notch filter can be used to remove it. The tone can be due to a heterodyne of two signals mixing or someone tuning up. The approach is to switch on the notch filter and rotate the control until the tone vanishes or is attenuated. If the tone frequency changes you will need to re-adjust the control.

Some radios have an auto notch feature that can automatically track tones and remove them without you needing to touch the controls.

A notch filter can adversely affect the quality of the received audio so should not be left switched in if it is not required. Also, listening to a CW or PSK 31 transmission with auto notch engaged can be totally self-defeating as the rig does its best to remove the very signal you are trying to listen to!

Receiver Incremental Tuning or Receiver Independent Tuning is a way of changing the frequency your radio is listening to without affecting the transmit frequency. It can be very useful on SSB if someone comes back to your CQ call and is not quite on your frequency.

By engaging the RIT and tweaking the control slightly you can make their voice more intelligible. If you moved the main VFO dial the chances are that they would change their radio and you would be back where you started.

The only problem with RIT is forgetting that you have engaged it. If you then subsequently move up or down the band to call someone else you will be off frequency. So either switch it off or set it to 0.00 kHz offset

Webmaster note- Personally I think the Rit is an instrument of the devil, I avoid its use all the time. How many times have you listened to a net where several of the participants have a the RIT engaged and each are netted on a different station — chaos and unintelligibility on a large scale.Forgetting to return the control to zero once used could account for your lack of HF success with the RX shifted possibly, by up to to 5KC either way, could lead you to wonder why there are no responses to your CQ calls!


The Automatic Gain Control is often misunderstood. Received radio signals can vary wildly in their strength, from very weak to incredibly strong. With AGC the radio will try to adjust itself to deal with these vastly differing signal strengths.

On the whole it does a good job, but you can help it. Usually you can choose between fast AGC and slow AGC. This affects the speed at which the radio will adjust itself when listening to different signals. While slow or medium AGC may be fine for SSB transmissions, you may find with CW or PSK31 that you miss the first one or two characters of a transmission as the AGC fails to react quickly enough when moving from a strong signal to a weak one.

Fast AGC tends to work better with digital modes, but it is worth experimenting. AGC can be a personal thing—I prefer a slow setting.

Width Control

All rigs work in different ways, but most will let you adjust the width of the IF filter. Other older radios may have different crystal filters that have the same net effect. These effectively cut down how much of the “band” you listen to at once.

Typical values for SSB tend to be 3.6 kHz or 2.7 kHz. The first setting is a broad filter that will give you excellent received audio quality. However, if the band is busy you may find that you suffer from adjacent channel interference and the 2.7 kHz setting might be better. With most modern radios you can even narrow this down even more, but if you go much below 2.4 kHz the audio will start to deteriorate.

If your radio lets you set up three different width settings for SSB then 3.6, 2.7 and 2.4 kHz would be a good choice

For CW and digital modes you might want to opt for narrower filters. CW enthusiasts usually go for 500 Hz or 300 Hz, although modern Software Defined Radios (SDR) can even be used down to about 50 or 25 Hz on CW with no “ringing”. Other people prefer to engage a 1000 Hz filter so that they can hear other stations that might be close by, using their brain to filter out the different signals.

The correct filter for digital modes, such as RTTY and PSK 31, will depend upon the mode itself and how busy the band is. A good choice would be set up three—say 500 Hz, 300 Hz and 200 Hz—and select whatever works best for you at the time. But setting a 3.6 kHz width would also let you hear signals that are close, but not exactly on your frequency.

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Clubs new Kyham Sports shelters christened

The new tents were erected swiftly and proved the point, they really are quick erect structures.

Having the two also worked very well at the WESS Rally at Stithians.

Thanks go to Trevor G4BHD for the photos

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Christian Volle’s visit to August meeting

Hello Ken,

we returned safely home to Munich last Thursday. Thanks for the nice evening
at the CARC, I had a lot of fun. And as I said – there is no difference in the
way these club meetings run between your club and those three that I know over
here in Germany – despite the language. That’s what I like so much, you almost
feel at home when you meet foreign hams.

After meeting you we have spend quite some nice days in Cornwall. We drove
the road from St. Just to St. Ives as you recommended and we took the time
to stop at various places. Indeed a very nice route. We found that Falmouth
is a good place to stay for a holiday, even at rainy weather.

We also visited the telegraph cable museum and, what I found most interesting,
we also saw the museum at Poldhu and a few days later the rebuilt marconi shack
at Lizard Point. In both cases we met the same very nice gentleman who took
the time to explain everything. I forgot his name. He is a ham aswell and lives
in a house very close to lizard point directly at the cliff. Perhaps you know him.

However I promised to send you the spread sheet file for calculating
radio ranges
Today I found the time to modify my calculations to work with imperial units
(miles and feet), as this seems more conveniant for you. I put everything onto
my very small website for download: http://www.qsl.net/dl7ayd/
Please forward this link to those who attended the talk or others who may be
interested. And please let me know if something doesn’t work.

I am very curious to see the photogaphs one of the OM shot at the club meeting.
Could you please forward them to me?

Please tell my very best regards to the CARC team! We spend an enjoyfull evening
with you! Hope to see you again one day. Tell me about your upcoming field day
events. Perhaps we can organize a sked on hf.

73 de Christian, DL7AYD

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One off offer to CRAC members

Another chance to save.

UAS Enterprises Ltd

BHI NES10-2 MK3 Noise Eliminating Speaker £75.00



The NEW NES10-2 MK3 Noise Eliminating Speaker replaces the MKII version
and removes unwanted background noise, hiss, hash, QRM, QRN, computer hash,
plasma TV interference, white noise etc from speech, so that you can hear
more clearly and listen stress free. Works accross all radio bands and is
also suitable for shortwave listening and for use in radio base stations.
The MK3 has a new rotary filter control knob on the rear of the speaker
that replaces the DIP switches that were on the MKII. This makes it much
easier to change the filter level whilst using the speaker.
The NES10-2 MK3 greatly improves the clarity and intelligibility of speech
in a variety of radio communications applications and is suitable for use
with most two-way radios as well as many other similar applications where
background noise and interference give rise to poor quality reception.
The power on/off audio bypass switch removes power from the speaker and
bypasses the audio allowing the speaker to be used as a normal extension
speaker without DSP.

  • Fully Adaptive noise cancelling
  • Power on/off switch with audio bypass
  • Noise cancellation 9 – 35dB
  • 8 user selectable noise cancelling levels
  • New rotary filter control knob
  • Compact robust speaker unit
  • Greatly improved signal to noise ratio
  • 3.5mm mono headphone socket (will drive another speaker)
  • Easy to install with adjustable mounting bracket
  • Noise Cancellation on / off switch
  • 12 – 24Vdc operation
  • Input sensitivity control
  • 2m audio lead

NES10-2MKII bhi DSP Noise eliminating Speaker with DIP




NES10-2MKII bhi DSP Noise eliminating Speaker with DIP selective filtering
settings, with new power on/off switch with audio bypass * Speaker with bhi
unique built-in fully adaptive DSP noise cancelling technology * Noise attn.
9-35dB * Dip switch settings for 8 filter settings * Power on/off switch with
audio bypass * Audio connection 3.5mm mono jack plug, 2m lead * Plugs directly
into 3.5mm speaker socket * 3.5mm mono headphone socket * Requires 12-24V DC
at 500mA max * Size 110 x 65 x 55mm * Weight 200g * Supplied with fused DC
lead * Can be used mobile with cigar adaptor (1030-VEPL) This is a combined
speaker and DSP unit that can be used with any receiver or transceiver. It
offers 8 filter settings selected via a dip switch on the back and a top mounted
on/off switch to select the DSP in and out of circuit.The power on/off switch
removes power from the speaker and bypasses the audio. This allows the speaker
to be used as a normal extension speaker without DSP. The unit offers dramatic
noise reduction enabling weak signals to be cleaned up by removing most of the
noise, audio hetrodynes are also greatly reduced. DX and weak signals can sound
just like locals. It is equally great for mobile use by reducing noise and making
speech clearer. And as a result of bhi’s unique DSP noise cancelling technology the
voice quality is superb with virtually no distortion even when there are high
levels of noise present.

01209 844859

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CRAC Rally 2013 – 7th July

A timely reminder to everyone. Rally 2013 is fast approaching and we will
be visiting the site next Saturday to manhandle the tables into position and
on site from early Sunday morning to meet and greet at first the Traders and
then our buying guests.

Doors will open at 1030am and we request that you all remember that and don’t
try to gain entry before that time. We need time first thing to allow everyone
to ready their stands for the visitors and to lend them a hand. We do not need
to be troubled by unauthorised visitors before the official start time as sorting
them out takes manpower away from more essential tasks. If you find yourself
asked to wait at the main door or to go back outside please comply with grace.
So have a lie in, don’t arrive at 9.00am and expect to come in immediately.
Opening is at 10.30am. We reserve the right to open earlier if all traders
are ready for the off and weather is particularly inclement.

Entry cost has been held at just £2.00 again this year even though the cost
of hiring the School seems to increase every year.

Opening time is 10.30 am

Items intended for sale on the bring and buy can be logged in before opening
of the show via the side entrance. Be prepared to pay a non returnable
administration fee of just 50p per item lodged for sale. This will help t
o cover our expences and deter entering numerous low value items for sale.

Whilst we take every possible precaution selecting traders for the show we
can not be held responsible for items purchased that are not fit for purpose.
So as buyers it up to you to carry out some due diligence and ensure you are
buying what you think you are buying and not a potentially expensive doorstop.

Contact details should appear within the programme and if you do have a problem
please contact the trader direct and not CRAC.

We hope to see a good crowd on the day as it is not just a trade show but an
annual social event giving everyone the chance to meet personally with and put
a face to the regular contacts you have beet talking with on a day to day basis.

So see you all there:

Cornish Radio Amateur Club Rally
Penair School

Sunday 7th July 2013 — opens 10.30am — closes when the traders
decide to pack up their wares. My suggestion is to come earlier rather
than later as in the past few years we have been packed away earlier each year.

To wet your appetite I can confirm attendance by

Henry Westlake for all your antenna, coax and hardware needs
Devon DX Group — good 2nd hand source
Worsley Communications – a local supplier of Amateur Radio equipment
Peter, formerly Garex
Kevin and Margaret from Bristol — general equipment

and more !

Refreshments will again be available from Colin’s catering van in the car park.

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AR 8600 MK2 – For Sale by member

I can confirm aAOR AR-8600 MK11 complete in the box
with software, all cables etc.

for which I want£575.00 ovno

Certainly hardly ever used (less than 10 months old) with no damage.
Various lists of Air and Marine frequencies to programme in available FOC



530 kHz ~ 2040 MHz (MK2 = 3GHz)

AR8600 specification

Frequency Range: 530 kHz to 2040 MHz

(Actual frequency input 100 kHz to 2040 MHz,

performance between 100 kHz to 530 kHz is

not guaranteed).

Receive Modes: WFM, NFM, SFM, WAM, AM, NAM, USB, LSB, CW


500 kHz ~ 2.0 MHz

AM: 3.50 ?V (10dB S/N)

2.0 MHz ~ 30 MHz

SSB: 1.50 ?V (10dB S/N)

AM: 2.50 ?V (10dB S/N)

30 MHz ~ 470 MHz

SSB: 0.30 ?V (10dB S/N)

AM: 0.70 ?V (10dB S/N)

NFM: 0.35 ?V (12dB SINAD)

WFM: 1.00 ?V (12dB SINAD)

470 MHz ~ 1 GHz

NFM: 0.50 ?V (12dB SINAD)

WFM: 1.50 ?V (12dB SINAD)

1.0 GHz ~ 1.3 GHz

NFM: 1.00 ?V (12dB SINAD)

1.3 GHz ~ 2.039 GHz

NFM: 2.50 ?V (12dB SINAD)

Selectivity: SSB/NAM 3kHz (-6dB), 9kHz (-60dB)

AM/SFM 9kHz (-6dB), 20kHz (-40dB)

WAM/NFM 12kHz (-6dB), 25kHz (-40dB)

WFM 150kHz (-3dB), 380kHz (-20dB)

Power Consumption: 350mA (nominal)

external 12 – 14V d.c. centre positive, negative ground

Dimensions: 155(W) x 57(H) x197(D) mm excluding projections

such as feet and knobs

Weight: 1.5kg

Memory channels: 1,000 (20 banks)

Select scan channels: 50

Priority channels: 1

Search banks: 40

PASS channels: 50 per search bank + 50 for VFO search

Scan/Search Rate: Maximum 37.42 steps per second

Specifications subject to change without notice due to
continuous development of the receiver. E&OE.

Please contact: John G1FVF

01209-213962 john

Very best 73

de John G1FVF

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Club Member offer

UAS Enterprises Ltd


Moonraker price £39.95 members price £35

· Type: Aluminium swaged pole

· Length: 4 x 5ft sections

· Diameter: 32mm OD (1.25 inch)

01209 844859

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UAS Enterprises Ltd


Moonraker £59.95 … members price £52.95


· Type: Portable aluminium mast with tripod

· Length: 4m open 1.5m closed

· Width of tripod: 1.5m

· Diameter: 45-38mm

· Sections: 3

· Weight: 4.1kg

· Load: 50kg

01209 844859

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Offers for Club Members

UAS Enterprises Ltd

Currently in stock



· Type: Antenna dipole centre

· Size: To suit 25mm (1″) boom to 12.5mm (1/2″) round tube for elements

Perfect for making your own antennas



· Type: Heavy duty pole clamp for mobile antennas

· Fitting: SO239 socket

· Connection: SO239

· Mast: To suit upto 51mm (2″)

· Size: 10 x 10cm

· Complete with earth tag for earth wire connection when required



· Type: Heavy duty pole clamp for mobile antennas

· Fitting: 3/8th female fitting

· Connection: SO239

· Mast: To suit upto 51mm (2″)

· Size: 10 x 10cm

· Complete with earth tag for earth wire connection when required



· Type: Heavy duty aluminium telescopic mast

· Length: 20ft open 6ft closed

· Diameter: 45-30mm

· Sections: 4 x 170cm

· Weight: 5kg approx

Heavy duty mast – all sections anodised

01209 844859

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Special offer

Last posting failed, thing there is formatting in the original e.mail so trying again

UAS Enterprises Ltd

coming in this weekend


· Price to members £8
You are here:

· Home /

· PACK OF 10 x PL259 TEFLON & GOLD Small or large cable option

Bottom of Form

01209 844859

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