Archive for the Infrastructure Category

Glenn Martin MT-1845 Tower Documentation

Posted in Infrastructure, Manuals, RF on April 3, 2013 by brandon314

I had a difficult time finding this documentation so I’ll post it here for anyone whom may need it in the future.


This is for a Glen-Martin (G-M) MT-1845 50ft crank-up ground-mount tower. This is the same tower found on their TT-1845 (trailer mounted 50ft tilt over tower), but with a base plate for direct ground mounting.

PDF Document for Base Plate/Concrete Requirements: Chb13-18

PDF Document for Tower Specification Drawings: MT-1845



MT-1845 1

MT-1845 2

PIP-2424LC Pure Sine Inverter Charger Review

Posted in Infrastructure, Reviews on April 1, 2013 by brandon314

I recently purchased a PIP-2424LC inverter/charger w/ Solar charger off of ebay from the Taiwanese company MPPSolar.

Below is a review of the item (with photos).


We purchased two of these units, one with the network interface module, one without. Both of these units were connected to 24V DC AGM battery banks (two group 8D batteries in series each). They were independently powered from either phase of a 240V drop (each had their own 120V 30A breaker). 200A fuses were used with 00 wire on the DC inputs. The sine-wave from these units was actually quite clean (especially considering the design) and played well with all of our true-sine sensitive devices. We did find that during brownout, the device switched over at too low of a voltage (even though we set it to be 100V) and some servers/computers would actually drop while the switchover was happening. This obviously defeats the purpose of a battery backup inverter/charger for UPS use.

After ~6mo use, one of the units showed DC BUS FAIL and was emitting a terrible smell. It failed into AC only mode (inverter not functioning) so at least the computers stayed online. After working with the vendor ( they advised us to remove the cover and photograph the internals. Below are what we found.



These are two capacitors off the main DC bus right at the switching MOSFETS. It appears that poor wave-soldering caused intermittent connection, which lead to high resistance and when the units would drop into inverter mode, melting of the solder. These two capacitors were loose in the unit (had unsoldered/burned the leads off). The 3rd capacitor was loose but not fully removed.











Wave solder screens under the capacitors were burnt, showing a clear indicator of high-resistance connection. The capacitors were still fully functional when tested.


A shot of the PCB where the capacitors connect.



A photo of the MOSFETS showing that they are all in-tact.


Another shot of the MOSFETS on the other side, again all in-tact.

MPPSolar wanted us to ship them the PCB board so that they could then ship us a replacement (meaning even more downtime, even more expense, and us doing all of the labor in-house). Purchasing these units from outside the country is the risk you take and in this case, that was a bad choice.


In summary we determined that poor wave soldering on this unit resulted in premature failure. The difficulty in configuring the voltages at which the unit goes into changeover can be a large issue for people with sensitive electronics or applications where 100%  up-time is a requirement. I would suggest not to waste the money on these units as even though the tech support team is good with communication, you will find yourself shipping parts to/fro Taiwan on your own dime.

I would also HIGHLY suggest never using one of these units in a mobile application as the construction methods and soldering type is not adequately stable for longevity.

Connecting Ubiquiti Aircam to Synology NAS – Surveillance Station 6.1-2941

Posted in Computing, Infrastructure, Networking on May 29, 2012 by brandon314

How to:

This requires you to modify .conf files on your Synology NAS. If you are not familiar with how to do this or are not good in a UNIX terminal, you may want to investigate adding this package to your NAS before starting (for file editing):

Make sure both your UBNT Aircam and the Synology NAS are running most current (current date 2/20/2014) firmware/packages.

Start the SSH service on your NAS if you wish to SSH into it using Putty or some other flavor of client. Do this by logging into your NAS, selecting Control Panel, then clicking on Terminal. Select ‘Enable SSH service’ and click apply. Confirm that Surveillance Station 6.1 is already shut down before editing files (you can confirm this in the package manager)

SSH into your NAS by entering the IP address and using the default port. Username:  root, password: admin

Example: Type ssh root@ hit return and then wait for prompt and enter the password “admin”. Replace the IP address with your NAS IP address and if you have changed your root password (you really should) it will be something besides admin.

Navigate to and edit the following files (I used the vi command followed by a space and the file name):



Add under the {camera*list] (using vi, you click the insert button on your keyboard and then scroll up/down):


Then add, down below where the camera port/streams are called out:

      video source=”/live/ch01_0″
video source=video.cgi


Use ch00_0 for higher resolution video.

You then need to save that file (in vi, hit Esc, followed by a colon, followed by the letters ‘wq’ and then hit enter.

Next edit the following file:



It doesn’t exist (it will be blank and empty) however if you use VI (or similar editor) and save the contents, it will create the file for you.

Within that file, paste the following:

api = ubnt

channel_list = 1

default_channel = 1
resolutions_h264 = 640×480, 1280×720

default_resolution_h264 = 1280×720

fps_h264_[640×480] = 5,10,15,20,25,30
fps_h264_[1280×720] = 5,10,15,20,25,30
default_fps_h264_1280x720 = 10
default_fps_h264_640x480 = 10
default_image_quality = 5

h264 = rtsp

default_username = ubnt
default_password = ubnt

(Again, if in vi, hit Esc, then enter ‘:wq’ and hit return to save)

Restart your Surveillance Station 6.1 package and go add a new camera.

Select UBNT and Aircam.

Name your camera, enter port 554, your proper IP, and H.264 as your video type. Username and password need to match what you have set up on the Aircam in the web interface under video, RTSP Authentication (username/password). Synology only includes one free camera license per NAS unless you buy additional licences through them (search the web to find out more).

Hope you enjoy having your NAS directly talking with your Ubiquiti Aircam.


Delta vs. Wye, A Beginners Guide

Posted in Infrastructure, Power on February 21, 2012 by brandon314

This is a good quick and easy guide for learning the differences between 3-phase power distribution prominent in the US.


MEP-006A Exciter Diodes

Posted in Electronic Projects, Infrastructure, Power on October 27, 2011 by brandon314

Here are the two diodes I selected to replace the failed ones in my MEP-006A Military 60kW generator.


You would need x3 of each and I recommend getting a spare if you aren’t familiar with proper torque and are prone to breaking studs off components. One is a reverse connection of the other (designed 1NxxxxR)



1N1190 / 1N1190R Data Sheets



Three of one type are on one side of the aluminium rectifier mount, and the other three are on the other side. Make sure you use plenty of thermal conduction grease when making the connection.

Generator Project Update

Posted in Automotive, Infrastructure, Power on March 9, 2011 by brandon314

The generator (MEP006A) had a power-off failure recently.

Upon investigating, found that the exciter had received some serious overcurrent (melted the soldered connections on the diodes on the exciter winding) as well as may have fried something inside the excitation module above (big green box).

Need to perform triage and figure out what happened…but hopefully have this back online soon.


Upgrades thus far:

  • Replaced Primary Fuel Filter with Dual Element Glass (like on John Deere Industrial)
  • Replaced Secondary Fuel Filter with Single Element Racor Spin-On
  • Changed Oil
  • Changed Oil Filters
  • Checked Valves
  • Rebuilt Injection Pump (had bad seals on shaft and rubber coupler…very common)
  • Replaced bad fuel lines
  • Cleaned Connections on Fuel Pumps (problem area)
  • Serviced Cooling System (CAT Long-Life Coolant 50/50)

I am also working on building a tandem axle trailer just for this unit. The axles/rough frame was donated by one of the family friends Tony. Removed the decking (rotten) and narrowed the axles/frame by 1.5ft and shortened it considerably. I purchased new bearing kits, two new drums, four electric brake backing plates, and two new tire/wheel combos. I also purchased some upgraded lighting (LED all around) and trailer connectors/etc.  I got all 24V compliant lighting so I can power basic proximity lighting on the generator while it is running on a job-site or parked precariously. It will have a new frame horn (heavy duty) and unless stolen, jacking points on all four corners. I would like to do locking cable/tool boxes to store various associated items.

That is all for now! More updates when I find out what let the smoke out.


MEP-006A Manuals

Posted in Infrastructure, Manuals, Power with tags , , , , , on May 6, 2010 by brandon314

Posting these up so I can get my hands on them easily…and if anyone else happens to need them.


TM 9-6115-648-14&p

TM 9-6115-545-24p

TM 5-6115-629-14&p

TM 5-6115-545-34

TM 5-6115-545-12-HR

TM 5-6115-545-12