T&L Publications

Hi! This is my first post here! I have a AccessHD DTA1080 DTV converter box that I got for 75 cents at a garage sale. The converter box seems to have a problem with powering on. When I plug it in, the LED light on the front is very dim & flashes off & on every 4 seconds & when I press the power button, it does nothing. The first couple of times that I tried it out, I was able to get it to turn on after about 10, or so, minutes of having it plugged in, however, the problem seems to have gotten worse. I assume it probably has a bad capicator somewhere in it, however I can't tell which one it is (I can't find any that are bulging or leaking.). I used to have a APEX converter box that had the same problem & found out that it had a bad capacitor in it & was able to replace it & get it working for awhile.

Those DTV Converter Boxes have issues with the Capacitors failing in the 12V supply.
Also, The Opto Switch is also known to fail.
Part No# TNY277PN {It sells for as little as .60 cents}.


Signed Janitor Tzap

Ok, thank you.

Do you have an ERS Meter?

If you do, check the capacitors in circuit with it.
That way you can avoid having to pull the capacitor out of the PCB to check it.

Though, given the age of the converter box.
Re-Caping the power supply circuit wouldn't be a bad idea.

I've had capacitors that look physically fine.
But, when I looked at them more closely.
I found that they had dried out.
The capacitors had over heated, building up internal pressure.
This caused the rubber stopper to be pushed out just enough,
to let the electrolyte vapor escape.
Normally when the capacitor leaks from the bottom seal.
You'll have an oily mess on the PCB, just under the leaking capacitor.

Well, from 2003 to 2009 there were a bunch of defective capacitors that
had been put in to a lot of electronics.
They used water instead of oil for the electrolyte.
This would cause the capacitor to develop dendrites on the internal plates.
Which would cause the capacitor to fail after a short while, when being run in a circuit.
Thus, no oily mess on the PCB.


Signed: Janitor Tzap

Where are some places I could get good capacitors at. Would DigiKey be a good place?

Yes,
Digikey is a good source for the capacitors and the Opto-Switcher.

Just make sure to check the physical size of the capacitors.
Some of area's on the PCB can be tight for space.
So try finding replacement capacitors that are similar in size.


Signed: Janitor Tzap

Digikey is good if you can place the minimum order and not get overcharged. Just Avoid anything from china on ebay.

not just bad electrolyte, there are all sorts of ways to shave costs on the raw materials and QA when bulk manufacturing. The component industry in CN is still suffering from these bad choices. I'v seen US companies with T&Cs on their PO that say no Chinese capacitors written in the boilerplate in bold face not just in the notes.

Yet they still spam me with offers to buy their caps

About a Comcast DTA
Has anyone found a way to get the audio from the Comcast DTA? It only has a Ch-3/4 output, and I am willing to go 'in the box'.
Running a TV, for just the music, seems to be nonsense!

Lenp wrote: ↑Thu Aug 27, 2020 2:46 pm About a Comcast DTA
Has anyone found a way to get the audio from the Comcast DTA? It only has a Ch-3/4 output, and I am willing to go 'in the box'.
Running a TV, for just the music, seems to be nonsense!

What is the model number on the Comcast DTA?

Also, do you own it?
Or
Are you leasing it from Comcast?
{If your leasing it, Comcast doesn't like customers modifying they're equipment.}
{Even if it is considered obsolete.}


Signed: Janitor Tzap

you mean the little converter they give you for old fashioned TVs. The audio is part of the RF signal sent to channel 3 and 4 so you need to use an RF to Video+R+L demodulator somewhere, I doubt you can hack the Comcast box, its probably all one chip. Searched on "RF demodulator" and found some

try this
https://www.amazon.com/GE-38806-Modulat ... cs&sr=1-14

Likewise you can find HDMI to composite adapters that let you get to the audio without a video display. These are also useful for stripping the DMCA copy protection from the HDMI signal so you can show on a multiple displays. Comcast charges a second hookup fee for The HDMI converters though. I suppose you got one of the courtesy tuners back when the DTV conversion was hot.

Hey Lenp,
Does this look like what your box has for hook ups?


If So......
You could try getting the Audio out of the HDMI Jack.



Signed: Janitor Tzap

With the HDMI port it would be easy, but alas, there is no HDMI port, just RF and a 2/3 selector

Inside, is there a shielded box that is just before the RF output? Might be a mixer combiner that takes the A/V signals and converts them to Ch 3/4. At least that's what the old Atari consoles did.

Hmmm......................

Okay,
I found what looks like your DTA.

And trying to tap off the audio from the RF Tuner is going to be a nightmare.
But how about just running the RF-Out to the RF-In on a Stereo VCR.
Then you can use RCA Composite Out Jacks too get your Audio Stereo.
Here's a Vid on hooking up a old Atari 7800 to a Mono VCR.
https://www.youtube.com/watch?v=yV1iOjYcfvE


Signed: Janitor Tzap

This is just for reference since it is a very old system , but it may give some insight on what to look for.

https://www.instructables.com/id/ATARI- ... osite-mod/