Replacing the USB Connector on a Nexus 7 (2013 version)

Getting the charging cable to actually charge my Nexus 7 (2013 model) has been becoming Increasingly difficult. Having to balance the unit on a coffee jar and hang a weight off the USB connector at exactly the right point was a challenge. Searching the Internet I am not the only one to experience this issue. The recommended solution was to change the connector, as it becomes sloppy over time. I managed to find a connector for 1.49 off Ebay. Note the connector on the 2013 version is very different from the 2012 Version.

Guided by a Utube video I managed to get the Tablet apart, at a cost of broken finger nails, revealing the Innards..

The USB connector is on the lower edge. To remove the connector, first, using a sharp scalpel cut the 5 pins sticking out the back of the connector. If you do not,  you run the risk of lifting the tracks in further activities, The four lugs can then be desoldered and the connector removed. It is then a simple task to solder the new connector in place using a fine tipped soldering iron and thin solder. 

The Tablet can then be tested for correct operation before re attaching the cover. Mine charged fine and still produced video. Task completed

RTTY and PSK31 Transceive with a Nexus 7 2013

Thinking ahead to summer portable operation I needed a lightweight way of operating the "classic" digital modes PSK31 and RTTY. The Dell laptop was too heavy and bulky. Looking on the Internet I came across DroidPSK at wolphi.com. which should work with my Nexus 7. For $5.49 It was worth trying, especially as my 2013 Nexus 7 has a mic input on the 3.5mm connector. Initially I tried it on receive by holding the Tablet near the speaker of the KX3. It worked well but was prone to room noise.

Next was to try it on Transmit.  There is a circuit of the interface that Wolphi sells on their web site wolphi-link  but the radio side connector would mean redoing my radio cables as the standard I had adopted was a 5 pin DIN. Looking in the junk box I found most of the parts to build it and a visit to the local component store realised the 4 pole "TRRS" plug and socket. I used a 2N2222A for TR1, but anything similar will do. The circuit was built on a piece of stripboard. Receive worked fine and transmit audio worked fine IFF the KX3 was manually keyed.  Using the PTT input on the mic connector did not work. The keying transistor did not pull the pin close enough to ground. I reconfigured the ACC2 connector as a PTT Input and this worked, but would require 3 cables from the Interface box to the radio.

In the past I had experienced similar issues with the Elecraft K3 which I had solved by using a keying FET not a transistor, especially the Darlington type. So the Interface was reconfigured to use a 2N7000. Now the "VOX" worked fine.

I was so impressed by the app that I went ahead and bought the RTTY version DroidRTTY. This uses the same interface. The only problem was that I was unable to set "my info" qth, name etc. What the manual didnt tell you is that as RTTY only transmits upper case characters, you can only enter Upper case characters in the text boxes!

The interface should only be plugged in after the Tablet has powered up. Having a resistor attached to the mic input while booting puts the tablet in a test mode which removes the bias voltage used to power the Interface. This caused some head scratching!

Nexus 7 2013 Upgrade

I have had a Nexus 7 (2012) for around a year and use it much more than my IPAD. When I saw that there was to be an updated version with front and rear cameras and an audio jack that supports headphone and microphone (like the IPAD does) I thought of getting one. The list price was $229 for the 16GB WIFI version was offputting, so I decided to wait until the "Black Friday" (the day after thanksgiving) Sales period. In actuality I did not have to wait that long as I encountered a good deal the previous Wednesday.and ended up buying one for $189.99 shipped.

It took 2 weeks to be delivered due to the post sales bottleneck!  When I opened the package, the first thing to be noticed was that it was thinner and lighter than the previous version. When powered up the display was also crisper being 1920 x 1200 resolution compared to the previous1280 x 800. 

As advertised the 4 pole audio jack worked with my Ipad headphones on Skype. No more shouting at the tablet. This is promising improvement when using FLdigi app where previously you had to hold the tablet near the radio speaker which was prone to background noise.

There is no HDMI output on the Nexus 7 2012. However reading the online reviews of the 2013 model it has a slimport jack on the bottom (looks like a microusb connector to me) and an HDMI adaptor can be bought. Searching on ebay I found one for $18. I did make sure i got one where you can charge the Tablet with a monitor hooked up. This works well and allows videos to be played on the living room large LCD TV.

The only wish list item I would like is a microsd slot to extend the storage, however I can use it with the RAVPOWER WIFI disk as previously mentioned which ups the storage to 500MB.