Friday, December 29, 2023

Blowby before+after treating with CRC and Seafoam.

I seem to have found a fix for my Equinox burning so much oil.  I did a video showing the blow-by before and after treating with CRC GDI Intake Valve cleaner and Seafoam. I added a can of seafoam to less that 1/4 tank of gas - thats twice the recomended mixture. When I was done with both things there was black suit on the pavement near the exhaust pipe. Blowby was reduced dramatically. Before the paper would float an inch above the oil fill opening after treating the paper covered it with no problem.


I had been using cat cleaners with every fill up for years!  Sometimes it would work but it was perhaps counterproductive.  With all the blowby the catcleaner would get into the oil and thin it out.  Then more oil would get burnt and dumped into the catalytic converter.  So I fianlly found a way to treat the problem at the source. 

I think the CRC cleaner might get to the rings as well.  However there was some brown foam coming out of the port where I was spraying the Seafoam into.

 Here is before and after readings on the lower O2 sensor. 

The O2 sensor did go back to spikeing after driving for a while but the check engine light is still off.

Wednesday, December 20, 2023

Using LED's to replace the flourescent bulbs in a street sign

UPDATE: the 5630 LED's are burning out after only two months of operation!

I have been using LED strips to replace the flourescent bulbs in a street sign.  My first attempts was to wrap the LED strips around the dead light bulbs.  That did not work that well.  My next attempt is to make a signboard and cover it with eight LED strips on each side.This will require 12 volts at 20 amps to run it! I switched the power to wire nuts and 12 volt 10 amp power supplies after this picture was taken. The barrel connectors in the picture got really hot.

This is the sign with the old LED strips wrapped around the bulbs.

This is the LED's that I am using in the new sign lighting panel.

WARNING!  The finished product was Light Blue in color, not white as was expected.  I am not sure what caused that as there are multiple power supplies involved.  However my pictures show it as whte.

Another issue is that the LED strips are falling down!  I had glued then with E6000 glue in at least three places (Each end and in the middle) but that and the adhesive that came on them were not sufficient!

Bad news: After only two months many of the LED's have burned out!  It cannot be the power suppy as there are two of them from different companies.

Wireless Bridge CPE for a Link to another building

 I just installed a wireless bridge for a link to another building.  The distance was about 3/4 of a mile.  The results were excellent!  I had no knowledge of how to do this other than using repeaters to pick up internet from a house or two away.  This time I needed to reach a building that was a few blocks away.  

I used google maps to see if there was a straight shot between the locations.  Then I went up on the roofs but could not see all the way to the other end from either direction.  There was nothing visible in the way.  It was a narrow shot as some pine trees surrounded my house but there was a gap in just the right direction.  

I bought a model that has lots of LED's on the side to be able to troubleshoot any issues.  I installed the "A" unit on the roof of my house.  Then the "B" unit (You can change A to B with a switch) was installed on the building.  I was amazed at the results the signal level was 100%!  But there was no internet at the receiving end.  The issue turned out to be that I had two internet cables at my house with a union in the middle and lost a connection somewhere.  Switching to 100 foot exterior grade cables at both ends resolved that issue.

Here is the ad for the bridge on eBay:

This is the receiving unit.  I made a PVC rooftop mounting bracket to hold it on the peak of a roof.

This is the transmitting unit on the roof of my house.

Thursday, December 14, 2023

Another amplifer rebuild with a TDA7394 Power Amplifier board

Once again I am rebuilding another amplifer this time with a TDA7394 Power Amplifier board.  I picked up theis fried amplifier at a Hmfest from a friend for like $10 for the poweer transformer.  I tested the output transistors and all but one were shorted.  So I decided to rebuild it with a dual TDA7394 amplifier board for $22 on eBay.  The power transformer is 60 VCT so the rectified power is + and - 42 volts DC.  That is a little high for the IC but within its specs.  It should deliver 100 watts per channel into 8 ohms without any problems.

Here is the old circuit board.  The preamp seemed OK so I decided to try to save it.

So I cut the old circuit board in half with a hand saw.

This is the new power amplifier board, it is a lot smaller than what it replaced.

This is the new heatsink to go with the IC based power amplifier.

Here is the finished amplifier.  All it is missing is the power on LED and a shielded audio cable from the preamp output to the RCA jacks on the back panel.  The preamp had a slight buzz in it, I don't know why.  Perhaps better shielded audio cables would help.