Can't Enter a Frequency

[kb9okb]

Perhaps this is a stupid question (I hope), but I can't for the life of me figure out how to program 144.002 MHz into an SDS100 (via the software or direct). It keeps changing it to 144.000 - how can I override the step settings and force it to enter that frequency? Thanks!

 

[doctordialtone]

force it to enter that frequency?

You can't.

• Configurable Band Defaults – Allows you to set the step (5, 6.25, 7.5, 8.33, 10, 12.5,15, 20, 25, 50 or 100 kHz) and modulation (AM, FM, NFM, WFM, or FMB) for 31 different bands.

See Specs - SDS100 True I/Q™ Digital Handheld Scanner


It won't matter. It's close enough.

 

[kb9okb]

Thanks for the reply. That seems like a horrible design. Unfortunately no, it's not close enough. Not even enough to break the squelch on 144.000 with a 0.1 mW transmitter at point blank range.

 

[doctordialtone]

0.1 mW transmitter at point blank range.

Any chance you're "Desensing" the receiver by being too close?

 

[wscranston]

That seems like a horrible design.

The radio is intended to pick up transmissions using standard steps used in the frequency bands of interest. It's not a "general purpose receiver" nor a ham radio.

 

[jaspence]

Why do you need that frequency? It is in the part of the band assigned to 2 meter CW and only a top end ham transceiver would be able to operate there.

 

[KevinC]

Thanks for the reply. That seems like a horrible design. Unfortunately no, it's not close enough. Not even enough to break the squelch on 144.000 with a 0.1 mW transmitter at point blank range.

Unfortunately it IS close enough. The scanner isn't selective enough to filter out some 2 kHz away. Most scanner can't even filter something 7.5 kHz away.

 

[wtp]

it is literally a whistle away...

 

[kb9okb]

It's a Red Fox 144 fox hunt transmitter running CW at < 0.1 mw. I can pick it up if I disable squelch entirely on 144.000, but at that power level it should be as spot on as it can get. Even the cheap Chinese HT's will all tune 144.002 on the dot.

 

[wscranston]

It's a Red Fox 144 fox hunt transmitter running CW at < 0.1 mw. I can pick it up if I disable squelch entirely on 144.000, but at that power level it should be as spot on as it can get. Even the cheap Chinese HT's will all tune 144.002 on the dot.

Can the cheap Chinese HT store thousands of channels, scan them at 100 channels/second, and decode several different trunking formats?Perhaps the scanner won't do exactly what you want it to do, but to call it "a horrible design" is really not fair.

 

[kb9okb]

Can the cheap Chinese HT store thousands of channels, scan them at 100 channels/second, and decode several different trunking formats?Perhaps the scanner won't do exactly what you want it to do, but to call it "a horrible design" is really not fair.

Amazingly they will do most of that, yes, just not all of the trunking formats. To be clear, you are misreading my comment. The "horrible design" is that Uniden decided to restrict the frequency entry to a minimum of 5kHz steps. The rest of the scanner is decent in my opinion. Far from perfect, but I wouldn't have shelled out over $600 for it if I thought the whole scanner was a horrible design, lol.

 

[KevinC]

As a test I generated 144.002 on with my Anritsu at -10 dBm and set my SDS100 to 144.000 and it receives it just fine. It's odd that yours won't receive it.

 

[mancow]

It's a Red Fox 144 fox hunt transmitter running CW at < 0.1 mw. I can pick it up if I disable squelch entirely on 144.000, but at that power level it should be as spot on as it can get. Even the cheap Chinese HT's will all tune 144.002 on the dot.

Doubt it. They are just showing you what you want to see but the single chip receivers are still stepping at 2.5 kHz.

 

[wtp]

did you try 144.005 ?

i found this later.
ARDF Transmitter, Micro-Power Beacon, 144.005 MHz, 500-700m Distance, Each
it does say 144.002 in the paperwork.

 

[kb9okb]

did you try 144.005 ?

i found this later.
ARDF Transmitter, Micro-Power Beacon, 144.005 MHz, 500-700m Distance, Each
it does say 144.002 in the paperwork.

Yeah it's fixed at 144.002 - can't change it. That would solve the problem.

 

[wtp]

but, did you try 144.005 ?

 

[Ubbe]

I think it would be pretty much impossible to get get -10dBm signal in the scanner from a 0,1mW transmitter. The transmitter connected directly thru coax to the scanners antenna connector would give a 0dBm signal and if only touching rubber antennas, if the hunt transmitter would use one, would give less than -10dBm.

But that said, my Uniden 536 are 1KHz off in frequency and my TRX-2 are off by 1KHz in the other direction and it's impossible to detect any problem at normal modulation levels. At 2Khz off I need to slightly overmodulate, from 5Khz in FM mode to 6KHz to be able to notice a slight difference when the filter starts to be used to it's limit. It can't be more than 1 or 2dB degradation when the signal are 2KHz off.

/Ubbe

 

[tvengr]

Enter the frequency as 144.0025. That is only 500 Hz off instead of 2 KHz and is within the FCC allowable frequency tolerance for 150 band commercial radios. It will have a negligible effect.

 

[Ubbe]

Enter the frequency as 144.0025

Is there a Uniden scanner that has 2,5KHz step size?

/Ubbe

 

[tvengr]

Is there a Uniden scanner that has 2,5KHz step size?

It works on my SDS, x36, and P2 scanners. My 996XT will take only 144.000 and 144.005.