Feedback Request: Common Cable Lengths

If you have your LNB stationed away from the Dreamcatcher, how much cable is in between the two?

We are considering including a length of cable in the kits.

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I have 40 feet of RG-6 Quad between my Maverick I LNB and DC 3.05. I tried to use a “universal”, but could not get good SNR with it, even up close.

What are we talking about here? I have 500 feet of RG6 between my Maverick and my Dreamcatcher v3.05. Works fine. Ken

We’re talking about average length for normal setups. For most cases, this is probably under 10 feet.

What is the typical reason for anything past a short pigtail?
I would guess typical in-beam hobbyist/tester setup is a Dreamcatcher near power or on a desk and the bare LNB at a window for good aim and less loss than through a wall so yea 10ft/3m.
That or an all-in-one water resistant out of doors adventure rig like Kenbarbi has, maybe has some extra cable to separate the antenna/LNB but maybe not.
When it comes to design we should try to remember the more interesting edge use cases where the off-the-grid possibilities inherent in the design come out, here is also where the opportunity to grab othernet publicity by attracting the attention of reporters and having a ready to edit canned press release story about the only person with a connection or shipping a case of Lantern/Dreamcatchers to a disaster recovery situation.
How much cable would you wish for in a use case of relocating from a natural disaster in a pole tent on a cow pasture or an ARES operator in shelter on a football field or parking lot vs the hobbyist and software tester on a desk at home.
I have had the opportunity to work in and design equipment and kits for aviation and emergency services. I very often take inspiration from the design considerations for the WW-II OSS ‘spy radio’ https://www.cryptomuseum.com/spy/b2/index.htm
or the paraset radio
https://en.wikipedia.org/wiki/Paraset
Assume the kit will get knocked over and fall at least 1m in open and closed states, include double the spares and consumables you though you needed. If it is modular make it easily visually obvious if a module is removed from the case, include an inventory inside the lid of the case if possible. Include simple operating instructions inside or outside the case.
My setup is at the edge of coverage 15m cable to a roof dish(waiting for LNB) with a Dreamcatcher inside a house; I also have 5m cable and a second dish which I hope to make into a field rig.
For engineering thought remember that the LNB receives electricity over the cable to power a small downconverter but also an amplifier and re-transmitter, the ~900mhz retransmission never travels over the air and so from the rg-6 datasheet the DC power would drop below useful voltage long before the RF carrying the re-transmitted satellite data would be too attenuated by cable loss to receive.

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When the case is ready I cant see a use for coax unless a dish is needed. Right now the only need for coax is to get the dreamcatcher out of the weather. However to answer your question 20ft should cover most people’s needs while not being to much hassle for the people needing less.

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Providing a length of coax to make a complete package is not a bad idea. along with a power supply and sd card. Make it an “out of box” working package.

Since typical RG-6 has a “nominal attenuation (or loss)” of 6dB per 100 ft at 1000MHz

I guess… 20 ft would get most installs for mounting the lnb outside. But include the outdoor mounting bracket.

I dont know how common the ability to strip and stick ends on coax is, I feel like pretty common among anyone geek-hacker enough to order a Dreamcatcher.
I would prefer a number of meters of RG-6 and two or four easy screw on F cable ends. I think most of us can do what is needed with that included and even a kitchen knife if needed.
Maybe give an option though that complicates ordering/delivery; I think a 30cm pigtail and a 5m set would work for anyone who did not need an outdoor install and both could be used for people who have a satellite finder beeper gadget. If you need to already use a dish I think we can expect the user to find sufficient cable for rooftop install too.
RG-6 and the connectors are common but can sometimes be difficult to find in a small hardware store.
I feel like a few meters of cable to reach a remote window suction cup mount or the tripod we have seen pictured in other threads so the LNB can either be in the case or connected remote as needed. For the additional price and weight of a few extra meters of cable the options are nice.

note:
If we do plan for people doing external LNB installs we should plan for some sort of bulkhead connector option; even if it is just putting the N female sticking out of a sized hole in the case and screwing the male side tight to tighten it down.

I don’t think you should include any cable, it adds to the shipping weight and everyone would want a different length.

Currently my receiver is at the end of a 40m run - what I would suggest is instead you offer an option of shipping by airmail as mine took ‘some time’ to arrive.

At least in the USA and EU cable is readily available and screw on F connectors are easy to apply. If you want to include something cheap and useful add three inches of self amalgamating PVC tape to wrap over the outside F connector on the LNB. People don’t think of that and it makes a huge difference to things as it prevents corrosion.

10/05/2019 9:02 Posting/Collection 60047
10/23/2019 8:39 Departure from transit of exchange PERTH
11/22/2019 8:41 Arrival at inward office of exchange GIBRALTAR

Better than PVC tape is some of that antenna cable putty you can get at amateur radio shops.
like this:
http://www.naval.com/coax-seal/
I will say I was fortunate to be in a large semi-urban area where after visiting 5 hardware shops over several hours and getting past a language barrier I finally found a shop with RG-6 on the spool and F connectors the day I picked up my Dreamcatcher package from the post office. Now that we are post analog TV HDMI cable in various lengths is in every electronics and hardware store, old cable TV/VCR hookup coax with F ends not.
I would have felt disappointed had I needed to order even a cheap RG-6/F pigtail from China and have to wait potentially months for it to arrive assuming it were not lost in transit.
On the other hand I feel like an othernet approved 2amp USB charger might be nice even as a pay for option since it causes so many low-power issues though at least in theory a 2amp microUSB charger is very available as various power option fast chargers for smart phones in nearly every small shop worldwide.
I feel like not even including a <$1us 30cm tested pigtail can create a situation like a kid on a holiday getting several electronic toys but having to wait a week for the special batteries or an unusual charger.

Let me clarify, I am not talking about standard electrical PVC tape, but self amalgamating tape which is used to protect exposed antenna connectors.

Anyone who does not use that to protect exposed satellite F connectors will have problems. It would be a nice idea to include a length of it as its cheap and low in weight. Its not something that anyone who has not done professional antenna work might be aware of. BUT it is the stuff and I’ve taken down antennas protected with it after 10 years and the connectors were ‘as new’

TV antenna coax is not the prefered stuff for connecting LNB’s to satellite receivers because its designed to be low loss and often has an air dielectric wheras a solid polyethelene is better with a shield. CT100 or WF100 is the stuff for medium runs although for a short run almost anything will do.‘RG6’ tends to be a generic term and the cable itself may vary in quality and performance. However the good news is the drive from the LNB is quite high so some cable attenuation is not usually a problem.

The migration from analogue tv to DTT still requires an antenna and a cable but perhaps for people with cable or IPTV antennas and downleads are historical.

Including a power unit is a bad idea because of the wide range of voltages and connectors on the world market and because of mobile devices and the raspberry pi <4 compatible ones are widely available. Its worth mentioning that although the power adaptor might be rated at 2a some cables will limit the power delivered to the device.

My receiver came with a pigtail from the board to a male F with an adaptor so was ideal.

You are building this kit to a budget, right? I’m use the cheapest pre-made length that you can get around the 20ft mark.

Modern power supplies will work worldwide. The plug is the only issue.

Since most problems with power comes from low voltage I wonder if it would be possible to add a buck circuit that would step the voltage to 5.1v. I know that caused interferance problems on L band. I wonder if that is still the case.

I can buy a 2a power supply from a pound shop (guess the price) It would cost more to ship and adds to the cost of operation and stock holding.

OTOH if you buy tape its around GBP 5 plus delivery trade and 10m may be more than most people need …

https://cpc.farnell.com/pro-power/sh5007sat/tape-self-amalgamating-19mm-x/dp/CB14492

15 meters here/

Weight of the shipped package is definitely something to be aware of. There are various cutoffs, but the top limit is 1 kg/2.2 lbs. Other weight cutoffs (for shipping cost reasons) are 8 oz and 16 oz. The enclosure by itself is pretty heavy, so we are stuck with the 1 kg limit. Depending on weight, there might be a 5 - 10 meter length of cable included. Probably not RG-6, as it’s too stiff and thick. RG-59 and RG179 are options, though.

@Syed, I like the RG179 option. Is it expensive, and does it have a much greater loss in dB per meter at 2.2 Ghz than RG6 Quad or Rg-59?

RG-179 is over twice the price of RG-59, but it’s pretty thin, so there might be a considerable weight savings at 3 meters of it. RG-6 has the least amount of loss. RG-59 is about 50% greater. RG-179 is 3x the loss of RG-6. But this is at 100m of cabling. The actual loss in absolute dB will not be as significant at the shorter cable lengths.

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I thought about rg179 before. Its thin enough that a reasonable length should fit inside the enclosure. I find any premade cables and didn’t want to make my own.

25’, but it would have been far more convenient at 50’.
I’d like to see option to add reflector / cones / cables / sdcard / loaded sdcard