Search found 67 matches

by alanzfq
Wed Oct 16, 2019 6:41 am
Forum: RTL-SDR Discussion
Topic: More on Showing wave form on an oscilloscope.
Replies: 8
Views: 669

Re: More on Showing wave form on an oscilloscope.

Presumably that software will compare two audio signals from the two synchronised receivers?
Alan
by alanzfq
Tue Oct 15, 2019 8:16 am
Forum: RTL-SDR Discussion
Topic: More on Showing wave form on an oscilloscope.
Replies: 8
Views: 669

Re: More on Showing wave form on an oscilloscope.

The youtube shows a simple way of getting an equal distance. Measuring between antennas is not simple. I can not give you instructions but I think you will need two identical locked receivers and then compare the outputs. I do not know where to take the output to be able to preserve and observe or m...
by alanzfq
Mon Oct 14, 2019 6:44 am
Forum: RTL-SDR Discussion
Topic: RTL-SDR Stops working
Replies: 2
Views: 289

Re: RTL-SDR Stops working

Bad cable?
Bad joint on USB plug?
Alan
by alanzfq
Thu Oct 10, 2019 8:46 pm
Forum: RTL-SDR Discussion
Topic: SDR has clear strong signal, 2 Meter ham rig has bad signal using same antenna
Replies: 4
Views: 504

Re: SDR has clear strong signal, 2 Meter ham rig has bad signal using same antenna

My first thought is that your TR7400 is faulty.
It would be the first time a RTL was better than a good proper radio.
Alan
by alanzfq
Fri Oct 04, 2019 1:39 pm
Forum: RTL-SDR Discussion
Topic: odd dark spot on audio decode with hdsdr
Replies: 2
Views: 380

Re: odd dark spot on audio decode with hdsdr

It notches out constant tones.
Not good for data modes, it works too well.
Alan
by alanzfq
Sat Sep 21, 2019 11:19 am
Forum: RTL-SDR Discussion
Topic: Compare field strength
Replies: 3
Views: 515

Re: Compare field strength

What do you want to do?
Comparing signal levels to within about 1dB is easy.
Actual Field Strength will need a standard, few, if any, SDRs are calibrated.
Alan
by alanzfq
Sun Sep 15, 2019 6:54 am
Forum: RTL-SDR Discussion
Topic: Dongle RTL-SDR very hot
Replies: 3
Views: 621

Re: Dongle RTL-SDR very hot

What dongle? Does it have a bias tee? Is it switched on?
That would explain.
Alan
by alanzfq
Sun Sep 15, 2019 6:52 am
Forum: RTL-SDR Discussion
Topic: Listening to AM radio
Replies: 10
Views: 1617

Re: Listening to AM radio

No easy answer.
The RTL is a poor receiver, is wideband, overloads so gain setting is crucial.
And may need filters to keep out of band signals away.
Spikes are common, often just spurii, not actually real signals.

See the shop, ebay, Google

Alan
by alanzfq
Fri Sep 13, 2019 10:03 am
Forum: RTL-SDR Discussion
Topic: Listening to AM radio
Replies: 10
Views: 1617

Re: Listening to AM radio

It depends on what exactly a "sky-blue 820T2 & SDR module" is.
Is it advertised as doing direct sampling? Does it have an upconverter? Ordinary RTL modules go from 24MHz upwards.
Alan
by alanzfq
Wed Sep 04, 2019 3:46 pm
Forum: RTL-SDR Discussion
Topic: Meteor Image Issues
Replies: 4
Views: 658

Re: Meteor Image Issues