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A ten year old radio and no narrow/wide setting. That's surprising. Which radio is it?
2.5khz v 5khz Deviation on 2m Radios - confused.
I am new to Ham Radio and have yet to take my foundation course and exam. Meanwhile though I picked up a cheap rig. It appears that this radio is only programmed for 5khz deviation and will not give an option to set 2.5khz. I have tried to find a schematic for the radio to see if there is something that can be tweaked to change this, but so far have not found one. The rig is around 10 years old.
As I understand it if the radio can not be told to use a 2.5khz deviation, repeaters or other radios will lose a proportion of the top and bottom of any transmission and may mean in any transmission being filtered out and disregarded or being very quiet.
As I live in a remote part of South West Scotland which has a limited population, and also due to the fact that my antenna is going to be in my loft I am going to have to rely on my local repeater, in order to make any contacts. Is this going to cause me huge problems? would I be better cutting my losses and getting a new cheap 2m rig such as the Yaesu FT1900E?
I also notice that many of the handheld radios do not allow a 2.5khz deviation to be set?
Any advice would be well recieved.
A ten year old radio and no narrow/wide setting. That's surprising. Which radio is it?
Ok so it maybe just a smidge older :-)
Azden PCS-7000H
Type: Amateur VHF transceiver
Frequency range: TX: 140-150 MHz
RX: 118-174 MHz
Mode: TX: FM
RX: AM/FM
RF Power output: Hi: 50 W
Lo: 10 W
Sensitivity: AM: <1 uV (10 dB S/N)
FM: <0.19 uV (12 dB SINAD)
Selectivity: N/A
Image rejection: N/A
Voltage: 13.8 VDC
Current drain: RX: Max 0.6 A
TX: Max 10 A
Impedance: 50 ohms, SO-239
Dimensions (W*H*D): 5.5 x 2 x 5.5"
Weight: 3 lbs
Manufactured: 199x-199x (Discontinued)
Other: 20 memories. CTCSS encoder
Is this any good to you?
http://www.mods.dk/manual.php?brand=azden
Thanks G4LNA I have that, but it doesn't have any schematics in it and just says that the radio is 5khz deviation?Originally Posted by G4LNA
That's a pity, sorry I couldn't check first as you have to be logged it to download them. Most radios you can adjust, it is just knowing where and which pot. I assume you have had a look inside just to make sure there isn't a skeleton pot marked for adjustment?
I am not that brave! I haven't even grasped the stuff in the foundation book yet :-)
Understood
If you are taking the foundation, is there someone in your local club who can give you some advice? There is usually a wealth of knowledge in those places.
Take the radio along to your local club when you do your Foundation training, it will be a great way to break the ice.
Amateurs love tinkering.
Actually you have it backwards, if the radio is set to Narrow - the audio on simplex will be low.
When you have a radio set to high - it will be at it's maximum amount of transmit audio on either the repeater or the simplex.
ON the other hand, when the radio is set to narrow, the repeater probably won't care and it will transmit - sound as if it was on wide anyways.
That is because the repeater is the only thing you will hear when you listen to people talk on a repeater unless you are listening on the input frequency.
Even at that, repeaters by nature are usually built in very high places.
Most people do not have the luxury to build their homes in a place higher then the repeater antenna - hence the repeaters usually have better reception and coverage then a above the house antenna or antenna on a 20' - 50' tower beside the house - unless the person you are talking to is in the same neighborhood as you are.
Some of our repeaters in the UK don't like excessive deviation, they will just chop the audio off when it detects clipping on the receiver.
That makes perfect sense to me.
Because we are an Amatuer Radio service: in the USA, we are allowed to repurpose old commercial radios, as long as the radios are not modified to work in both the commercial and the amateur bands at the same time.
To use a example, Motorola service radios, lets use a Sinitar as a example, which has a deviation ratio that is set rather high for amateur use.
Commercial radios by nature are usually cranked up because the people setting up the radios thinks that if it is louder - it will sound better.
That works great with amplitude modulation, but causes too much deviation with FM.
On the other hand, foreign built radios - lets use Yaesu or Kenwood, their deviation levels are set high due to the fact that Japanese people tends to talk softly.
As long as you hold the mic away from your mouth and you talk in a monotone voice - your audio reports will always be decent - even FM. For those who thinks that they have to chew the mic to talk or talks loudly - all it does is causes distortion - hence makes it harder to understand the people you are trying to talk to - who is talking too loud or has their deviation level cranked up.
On the other hand, most mobile land radio service radios do not have the option of wide vs narrow.
Our Government - FCC came along and made a mandate that we reduce our emmissions - hence all wide band commercial radio was to stop after such and such a date. Here is where the problem lies.
In my area of the country, many of the fire and ambulance services was on the low bands - 33 - 48 MHz.
The reason for this was that the low bands would serve a larger area with less repeaters then the higher bands.
One good example is Indiana County Pennsylvania.
Low and behold the state police went to their own system called Open Sky, which is a proprietary system and works on the lower end of the 800 MHz spectrum.
Now they have to have a repeater antenna on top of a telephone pole every 5 miles to increase their coverage to the point of being able to do what they did for a entire county with 3 repeaters.
All of the low bands stuff will be up for sale once the switch is complete.
The problem is that the motorola stuff does not work - out of the box on the amateur frequencies - hence there is going to be lot's of it for sale on Flea Bay or sold to third world countries where they are not as politically correct.
In my county, they migrated all the public service stuff up into the 450 mhz part of the spectrum from the 46 - 49 mhz fire and 150 - 160 MHz police.
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