i have looked everywhere and i can't find if a bias tee will work on that or not..and i'm not really familiar with things like that. if that splitter would work it would cost me less to just buy that than buying the adapters .
SDRTrunk how many dongles do i need for P25 Phase 2?
- Thread starter Ronnierozier2
- Start date
Why not see how the j-pole does? It may bring in a nice signal where you would not need an LNA and bias t. Have you played with the gain anymore? Generally you keep raising the gain until the signal reaches its highest peak, and the noise floor just starts to rise, than back it off a hair.
yeah i was just thinking that i could buy the adapters for the same price as that splitter where i wouldn't need the adapters but i wanted to make sure the splitter would work with bias tee just in case i needed it. would that splitter i sent u work if i needed to power a LNA
To be honest, I really do not know which splitters can and can't pass voltage to lna. Im sure someone with that knowledge will chime in. I have a short run of coax where I use my LNA and it gets powered via a wall wart and if I travel its done via usb.
oh so u don't put your LNA close to the antenna?
I put it at the antenna, which is a 7/800 yagi, that's in my upstairs office and with in reach of external power sources. I have a discone on the roof and for the most part I get good signal on everything. My understanding with LNA is some are not pass thru, meaning they need to be powered on at all times to pass the signal thru. I am not looking to amplify my already strong signals.
I recently snagged this, and this in a raffle. The Lna would not power on so they are sending a new one. The HackRf seems pretty deaf and we have been doing testing on that. Keep in mind I have a few PC's running scanning and sdr software and have 2 outdoor antenna.
I recently snagged this, and this in a raffle. The Lna would not power on so they are sending a new one. The HackRf seems pretty deaf and we have been doing testing on that. Keep in mind I have a few PC's running scanning and sdr software and have 2 outdoor antenna.
yes i understand that, that's one reason why i ask you so many questions because i can tell you are far more versed in the subject. i went ahead and bought the adapters u sent me i am holding off on the LNA until i test and see how strong my CC are after i install the j pole. i'm not sure if i told u before but this https://www.amazon.com/gp/product/B07G14Q6XX/ref=ox_sc_act_title_4?smid=A37V0QGFC9C912&psc=1 is the LNA i'll probably get if i need it and it has to be powered by a bias tee. i did look at the one by nooelec that u sent and if i put one near my antenna i want to power it by bias tee because i don't want to run a power cord all the way to the antenna. another thing do u know if i can block a certain traffic on sdrtrunk. i'm getting department of corrections and i did mute them but i'd like to just stop the sdr from picking them up to free it up for other traffic. 'what would happen if i hooked the lna u sent me to the sdr instead of at the antenna? Thanks
Thats funny, I was about to get the rtl blog lna and then I won the rafftle. Still might get it because I travel and take dongles with me and it's a pain unhooking stuff. And when I get home, I just want to rest.
Did you import the system from radio reference? If so, open the playlist editor, go to the alias tab, select the list with the aliases. Tick off both listen and record. Hit Save. Do for each one you wich not to hear.
Did you import the system from radio reference? If so, open the playlist editor, go to the alias tab, select the list with the aliases. Tick off both listen and record. Hit Save. Do for each one you wich not to hear.
oh ok thanks...I was just listening to sdrtrunk and i had a dispatch come over and and then i heard it come over 3 more times back to back the same thing. wonder what made it do that i am locked onto 2 control channels 152.6825 and 161.800 i need to get this figured out because the 152 is farther away than the 161 by about 30 mins drive, should i keep locked onto both or would i be ok just locking onto one?
Never seen this device before, and I would not want to be the guinea pig to test it out.
Not sure that device would work. Your freqs are 150/160mhz..
Thanks i decided not to go with it afterall...i'm still having trouble understanding if i need to use both CC 152 and 161. like i said they are roughly 30 mins apart from each other so if i just run on one CC 152 would i still get everything or do i need to be on both CC . i'm not sure how that would work if 2 CC are close to each other like that as far as the traffic is concerned ... many thanks.
If both sites broadcast the exact same traffic, talk groups and each specific radio, then one site could work.. If radios on one side of the county (30 min away) are only affiliating with one site (30 min away) and not the other, you will miss stuff.
My county has a bunch of sites and on the 2 within my reach, I see some talk groups on all sites, and some talk groups on certain sites. The same with individual radios (units driving around). It all depends on where the radios are and which sites they are reaching. You are better off just using the 2 dongles. One 150 and the other 160. In my opinion the 3rd dongle is not needed because the the first 2 can cover everything.
| 2 (2) | 013 (D) | Honaker | Buchanan | 152.6825c | 152.7125c | 161.875 | 162.000 | |||
| 2 (2) | 017 (11) | Oakwood | Buchanan | 152.8175c | 161.800c |
What you can do, since the 2 dongles will cover both sites, is increase the max traffic channels setting on site.
Go in the playlist editor, select Honaker and look for the setting on the bottom and set it to at least 4. Then do the same for Oakwood. That one really only needs 2 but 4 will work in the event there are more voice channels than listed in the database. You should have 1 traffic channel for each voice channel on the site. On some systems control channels not being used as control at the time can be used as voice channels.
ok just to clarify i can't set both 152 and 160 CC to the same dongle? and i'm confused on the 152 CC and the voice channels for that site shows 161.875 and 162.000 if i'm set on the 152 CC will that dongle handle the 161 and 162 voice channels?
No. You cant set them to the same dongle. Your monitoring 2 sites. Both sites have 150 freqs and 160 freqs.
One dummy channel set for the 150 range will see and grab any activity (cc and voice) on the 150 freqs on both sites.
Other dummy channel set for the 160 range will see and grab any activity (cc and voice) on the 160 freqs on both sites.
1. You cannot monitor both control channels with the same dongle as the channel spread exceeds the ~2.4 MHz bandwidth of the RTL type dongle.
2. If dongle #1 is set to the CC for site #1 at 152.xxx, and dongle #2 is set to the site #2 CC at 160.xxx, the voice channels associated with site #1 will be received by dongle #2.
2. If dongle #1 is set to the CC for site #1 at 152.xxx, and dongle #2 is set to the site #2 CC at 160.xxx, the voice channels associated with site #1 will be received by dongle #2.
Awesome i have it set up exactly like that. also if i'm set to CC 152 and i hear police then i hear fire department so does the police also hear the fire department like i am? and i noticed the department of wildlife is encrypted why would that be encrypted it makes no sense.
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great i finally understand how this works now lol i'm slow to learn but i think i have a handle on it now..i have tested dsdplus fastlane but i keep coming back to sdrtrunk i think it is better. i wish there was a way to scan the fm freqs for police and ems but i havn't figured that out yet.
Generally, the police would not hear the FD unless a. their respective tgs were patched together, or b. a police officer was monitoring the FD's tg for some reason. Wildlife is commonly encrypted to keep poachers from monitoring their comms.
Short answer. If the fm freqs are within 1.2mhz of the freqs you set each dummy channel to, then yes and you would create a nbfm channel in the play list editor and start it after you start the dummy channel
Long answer well it’s going to be short to cause it’s dinner time. Some of the freqs were labeled nxdn which sdrtrunk does not do. But you could set them up in a scan list in DSDPlus and use the 3 rd dongle. It would scan them like a scanner and DSDPlus does do nxdn.
