Thanks to PY2SDR for adding much LNBs to the list
73
Thanks to PY2SDR for adding much LNBs to the list
73
You need both for the LNB to work fine..
The first "mod" was only the half way
73
Now i modified the HD Line Black Premium LNB a little bit more and now it is good working.
I cut the pcb track which attenuates the 26MHz from the TCXO to much and added 2 coils with together ca. 15uH.
Now the LNB locks with lower ref signal and its gain is only abt 2dB weaker that that from an standard Octagon.
vy73 DB8TF
You can "hide" your address but names are always shown in that list.
Surfing the net, i found a PDF from a chinese patent, i can't read chinese but the chematics in this PDF look very similar to a chematic for a LNB with RT320M and single crystal.
https://patentimages.storage.g…cca8a520/CN206712931U.pdf
Not the best picture quality but readable
Maybe we can find a fix for a easier change of the LO?
vy73 DB8TF
Partly success on the HD Line Black Premium LNB. Inspired by OH2AUE's work.
Remove carefully the crystal and insert a simple bandpass as seen in the pictures.
Check if you have damaged the connection from the crystal pad to the via, if it is broken use a small wire to fix it.
Now the LNB could be used on both outputs with the external ref injected to the one you had choosen for connecting the bandpass.
The ext ref i use is the cheap toyocom TCXO from eBay which i have indoors and temperature isolated so it is relative stable (+/- 100Hz/h). The signal is fed with the known triplexer into the coaxial cable to the LNB.
With the 26MHz ref from the TCXO now the WB is shifted to the normal receiving range from a normal Sat receiver. (abt 1,106GHz)
It seems that the LNB gain has dropped abt 3dB, not a problem on my big dish, but on smaller dishes it would be not good. Maybe some additional resistors could improve the gain.
Vy73 DB8TF
To add Infos to the spreadsheet click with the right mouse button on the field and select "add commentar".
I will check the submitted data and put it in the spreadsheet.
vy73 DB8TF
There are missing a lot of LNBs which are in use actually.
Not one with TFF1017 is in the overview.
Just talked to a OM with a Goobay 67269 LNB and he sees also a wobbling in the spectrum. PLL used there is the TFF1017
We need to get a fix to that problem with the TFF107x ICs.
vy73 DB8TF
Inject about 100mW on the input and measure the output power.
Now use small pieces of copper foil on the input pcb trace for max output power and then add a small piece on the output trace. That worked best for me. Abt 16W with 0,5W drive. Takes some time but works.
First i tried with a network analyzer to optimize S11 on the input but then i only got 3W max out of that little PA.
vy73
Maybe it would be good idea to collect our experiences with LNBs for RX and concentrate them in a spreadsheet available for everyone?
I started one: https://docs.google.com/spread…gZRm2uxA/edit?usp=sharing
I restricted to comments only, but i will add the infos from comments to that spreadsheet if they are plausible.
vy73 DB8TF
Nice to see that simon keeps the promise he gave me months ago to implement this function
BTW he was the only SDR software programmer who even answered to my emails/answered in forum.
See here:
https://sdr-radio.groups.io/g/…7993?p=Created,,,20,1,0,0
vy73 DB8TF
No improvement with 12VDC on both connectors.
Still strong wobbling +/- 200Hz.
I will let it connected and warm up a few hours, maybe it get's better.
73s
I will check that later
All my Octagons have 2 outputs
Maybe with D75F or ext Ref it works fine?
I also don't understand why it wobbles but i have installed a small dish for testing various LNBs on the balcony and so i can quickly compare LNBs.
After the HD Line BP2 i installed a "old" Octagon and this works perfect.
CW Bacon crystal clear sound (clearly with drift as the LNB warms up).
Big difference between those LNBs.
Maybe someone with the right measuring equipment could determine why the LO on some LNBs is wobbling and on others not?. I would do it myself but my spectrum analyzer only works to 2,6GHz
73 DB8TF
Whats that for a strange signal just around the P4A transponder?
Every 10 secs i can hear a burst on AM. On the P4A passband i can't hear it.
VY73 DB8TF
EDIT: This LNB wobbles worse than the GM201 ! Don't buy it!
Hello OMs,
today arrived the HD Line Black Premium LNB.
And it is with 27MHz crystal and the RDA 3565ES PLL IC
No need to buy overpriced Octagons anymore. 17€ from Amazon, delivered from France to DL in 4 Days.
And it comes with 2 "golden" F-connectors.
vy73 DB8TF
Done the oh2aue mod on my GM201 and it works good.
But if you want to do this mod you need badass soldering skills
vy73 DB8TF
Nice polish forum with lots of pics from DRO & PLL LNBs:
https://satclub.pl/viewtopic.php?f=113&t=7274&start=70
vy73 DB8TF
Hi Michael, what does that mean:
BTW, yesterday i also tried to mod a GM201 for 1 cable ref Input.
Didn't work because i didn't mod the VIN stripline and add the 11Ohm resistors Today i will try again. I saw your PDF later
Today i went to 2 local electronics stores and measured some LNBs <30€.
Found 2 LNBS (Schwaiger) with 25MHz PLL
The third (Hama) seems to be a DRO type. (nothing on 25 or 27MHz found)