Page 1 of 2

18v h power

Posted: Sat Mar 09, 2019 7:05 pm
by m1cdq
Im thinking of fitting a small dc-dc buck convertor 12v to 18v
this is for the V/H on a lnb and make it switchable.. via a switch on the case

but Im thinking and i presume the output ground on the dc buck is isolated/floating from the input. and connecting this to the lnb power input on the board would bring the output group down to the min ground of the case. and this would defeat the upconvert to 18v

reason on thinking this route is i will be able to use it portable and not have to mess about with lnb all the time just switch it and be able to run from just a 12v supply

Re: 18v h power

Posted: Sat Mar 09, 2019 7:20 pm
by g8gtz
Hi

The typical ebay upconverters should common earth and can be used.

In fact, this is exactly what I have done to generate 12 or 18v from the 12v rail and switch it via a center off 3 position switch - center off makes sure there is no chance of shorting the 18v to 12v rail!

73
Noel - G8GTZ

Re: 18v h power

Posted: Sat Mar 09, 2019 8:29 pm
by m1cdq
cheers for the reply noel
If found non isolated ones so Im going to give it a try. Same as you a centre off 3 switch

Re: 18v h power

Posted: Sat Mar 09, 2019 10:44 pm
by g0mjw
g8gtz wrote:
Sat Mar 09, 2019 7:20 pm
Hi

The typical ebay upconverters should common earth and can be used.

In fact, this is exactly what I have done to generate 12 or 18v from the 12v rail and switch it via a center off 3 position switch - center off makes sure there is no chance of shorting the 18v to 12v rail!

73
Noel - G8GTZ
Hopefully, but beware of things with capacitors in them that charge to 18V and you then connect then to your 12V rail.

Mike

Re: 18v h power

Posted: Sun Mar 10, 2019 12:54 pm
by F6DZP
Hi,

Someone in France has made a pcb for adding the same LNB chip as it is used in the MiniTiounerPro, for adding the possibility to give 13v, 18v and 22kHz/diseqc messages to the MiniTiounerV2_BATC.
This chip is protected and we can use 400mA continuously.
I am adding the use of this extension in the config.ini for Minitioune V0.9

Jean-Pierre F6DZP

Re: 18v h power

Posted: Sun Mar 10, 2019 11:55 pm
by YL3AKC
I solve 18V problem cardinally. I have Twin LNB with Rafael Micro RT320M mixer inside. Similar to this LNB: http://www.pabr.org/radio/lnblineup/lnb ... LSO%201609

The idea is following: Each IF output have voltage sense pin connected to corresponding F connector. I found that there are 200K and 20K resistor dividers. So, when you apply +13V out get 0.9V on sense pin, and when apply 18V, you get 1.9V. What I want? I want that on one f-connector there is always H-pol and on second f-connector I want V-pol. Supply for mixer is made by two linear stabiliser ICs and then merged by 1n4148 diodes. So, I calculated divider and connected sense pins to diodes middle point (true VCC ~ 5.5V) 1st thing: find 220K (or 200K, I don't remember exact numbers) resistors and remove them. Then to get V-Pol (12V equivalent), connect between true VCC and sense pin ~91k resistor. To get H-pol (18V equivalent) use ~32k resistor. Now I have H and V outputs from LNB. And it desn't matter where you feed BIAS and doesn't what is bias voltage. I am using 12V BIAS voltage now, but considering to use as low as 7.5-8 V in future.

PS: Thinking to use CATV combiner to combine NB and WB signal in one coax cable and feed down to "radio corner" where are BIAS inserter (SPAUN and +12V), computers and transceiver.

Re: 18v h power

Posted: Sun Apr 28, 2019 8:50 am
by 2W0ODS
F6DZP wrote:
Sun Mar 10, 2019 12:54 pm
Hi,

Someone in France has made a pcb for adding the same LNB chip as it is used in the MiniTiounerPro, for adding the possibility to give 13v, 18v and 22kHz/diseqc messages to the MiniTiounerV2_BATC.
This chip is protected and we can use 400mA continuously.
I am adding the use of this extension in the config.ini for Minitioune V0.9

Jean-Pierre F6DZP
Do you have a link to this PCB please, I would love to put this in my BATC V2 build.

Re: 18v h power

Posted: Sun Apr 28, 2019 11:02 am
by Nick
I just use a E-Bay buck converter to get the 18V. The 18V output is fed to a 12V regulator with didoes in the common connection to get the voltage to 13V. The Bias-T itself was obtained from E-Bay.

Nick - G4NKV
Bias-T Inside.
Bias-T Inside.
Bias-T 1.jpg (1.19 MiB) Viewed 6067 times
Bias- T Front.
Bias- T Front.
Bias-T 2.jpg (904.67 KiB) Viewed 6067 times
Bias-T Rear.
Bias-T Rear.
Bias-T 3.jpg (739.14 KiB) Viewed 6067 times

Re: 18v h power

Posted: Sun Apr 28, 2019 1:40 pm
by G1LPS Terry
https://f5xg.jimdo.com/

link to the article on the pcb add-on to BATC V2 board.
That can be controlled from Minitioune V9 BETA 7

Re: 18v h power

Posted: Sun Apr 28, 2019 2:11 pm
by 2W0ODS
G1LPS Terry wrote:
Sun Apr 28, 2019 1:40 pm
https://f5xg.jimdo.com/

link to the article on the pcb add-on to BATC V2 board.
That can be controlled from Minitioune V9 BETA 7
Brilliant, thank you for the link.


Also is it possible for the BATC shop to sell these PCB's or something similar based around that chip?