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Important Notices and Custom Antenna Update

Important Notice for our Early Supporters: 

For anyone who ordered from our crowdfunding campaign early-on in November and December of 2019, we will soon be sending you an invoice for the shipping fee. 

When we started the crowdfunding campaign we used Stripe as our payment processor. Stripe did not allow us to charge shipping according to your location and we would have had to set a flat rate that would be higher than what it should have been for most countries. At the time of check out we had a notice that shipping would be charged at a later time. Now that we are getting close to shipping that time has come. When you receive the invoice make sure to take special note of your shipping address to make sure it is up to date. If not, please let us know by emailing us at support@source.parts

Important Notice for those who purchased the LoRa version of Pocket P.C.: 

Pocket P.C. with LoRa will ship a few weeks to a month after we start shipping the Wi-Fi / BT only version of Pocket P.C. 

Despite pushing our antenna vendor to shorten the lead-time for our custom antennas, they responded that they have limited factory capacity at this time due to a high demand for their products. We will keep those who purchased the LoRa version updated on the new timeline as soon as we are able to reschedule production with our factories based on this new information. See below for more information about the custom antennas.

We will be assembling the PCBs for all the units at the same time but will store the PCBAs for the LoRa version in our factories climate controlled warehouse until we receive the new antennas.

Community Update:

We have set up a Discord community for more real-time discussions and eventually AMAs with the team.

Everyone is welcome to join, ask questions and chat with other community members.

We only ask that you please avoid sending our team members DMs to ask about production or shipping status as our team has limited bandwidth to respond to these in the upcoming few weeks while we gear up for mass production.

Also, if anyone is having trouble with logging into popcorncomputer.com or posting to this forum, you may message @sourceparts on Discord or email support@source.parts and we will get that sorted out for you.

Here’s the link to join our Discord: https://discord.com/invite/3X7ZZufTvu

New antenna provides increased efficiency for 868Mhz and 915MHz frequency bands:

This update will review how we obtained the best range for Pocket P.C.’s radios and how efficient the antennas are. To provide a quick definition: Antenna Efficiency is the ratio of power radiated by the antenna to the power supplied to the antenna. An ideal antenna has 100% antenna efficiency, i.e., it transmits all the power fed to it.  But in the real world, a good antenna radiates 40 to 60% of power supplied to it.

In early May, we spoke to our antenna partner, Unictron, which makes all the antennas for Pocket P.C.’s radios.  We requested that they improve on the antenna they had initially developed for us.  That is the antenna we showed in our last update. We were getting an efficiency around 20% in the 868MHz and 915MHz bands according to test reports.  While this was an improvement over our original chip antenna we were using in earlier versions of Pocket P.C., 20% did not meet our expectations for the 868MHz – 920MHz bands.

Unictron returned back to the drawing board and requested two weeks at the beginning of May to do further research and development. We had initially planned to order the latest DVT PCBs around that time and were told that the position of the pogo-pins connecting the antenna to the PCB would not be moved but to be safe we waited until they got back to us until we proceeded. We were glad we waited because after their response about the latest antenna they developed, they said that this antenna would only require one pogo-pin and the position had changed slightly.  If we had gone ahead with the PCB fabrication and assembly before waiting for the test results we would have had to order another batch of PCBs and have them assembled. This would have delayed mass production even further.

And the results are in:

Antenna for 868MHz

41.9% at 868MHz

Antenna for 915MHz

42.2% at 915MHz

Unictron engineers are now able to achieve over 40% for both 898MHz and 915MHz frequencies with the newly re-engineered antenna.

Wi-Fi Antenna Tests

While Unictron was developing the new LoRa antennas, we asked them to test the efficiency of our Wi-Fi antenna. The results show an efficiency of over 40% for all Wi-Fi channels. We were pleased with the result. 

Additional Information:

In the following image you can see the antenna location in Pocket P.C. as well as an image of the prototype antenna that was used to obtain the information presented above and below. The antenna that will be in all production LoRA Pocket P.C.s will look like this:

We can learn a lot about how an antenna will perform from its patterns. The following are 3D gain patterns of the separate 898MHz and 915MHz antennas. If you want to learn more about these patterns and how they are used, there is a good document that goes into more detail by Cisco Systems and can be found here: https://www.industrialnetworking.com/pdf/Antenna-Patterns.pdf

To obtain these 3D Gain patterns, the following test setup was used in the Lab:

To obtain the efficiency of the antenna, the following test equipment was used in the Lab:

Final Thoughts

Overall, we hope that the real-world benefits for those who purchased the LoRa version of Pocket P.C. of waiting for an improved antenna design will be realizable in a longer effective range of the LoRa radio. For those who purchased the Wi-Fi / Bluetooth only version, the extra time spent this past May allowed Unictron to spend more time tuning and testing the antenna. Without this extra time, we would not have been able to achieve the efficiency that we received as a result of this test. 

This week our manufacturer will be producing the last DVT that rolls in everything we learned as a result of the previous two DVT revisions. Assuming everything goes as planned, we should be able to show a completed unit in the next week or so. Our software developers have already developed a significant part of the LCD drivers and as soon as they receive the sample units, they should be able to demonstrate Pocket P.C. booting Debian into a desktop environment on the LCD.


    I apologize for the longer than expected time between updates this past month.  You can expect more frequent updates this month and if you haven’t already, feel free to join us on Discord or in our community at https://community.popcorncomputer.com.  I greatly appreciate everyone who is patiently waiting for their Pocket P.C. and have shared their words of encouragement and support throughout the entire process. Thank you.

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