mickcris wrote:I did not design the circuit I am selling, but it does work wonderfully (I would not call it an improper solution but it is a bit fudged from the original circuit in the data sheet to make it look a little better). and yes I am going to say it, it has been installed on probably thousands of consoles with no issues.
cfx called it! Sorry about that!
I seem to recall that the specific design of that THS7314 circuit was based off of Tim's own suggestions on how to apply it to the NEC systems (AC Biased input & voltage divider output)!
mickcris wrote:I have only seen one other person besides you report that they have used it (leonk)
CkRtech has installed at least one in a Duo. IIRC, there was someone else as well that posted within the last month looking to get one installed. I'd imagine there are more, but certainly not as many when you compare it to something that is posted on many different forums!
mickcris wrote: he has said that there is no difference in video quality comparing the one that I sell to Tim's board.
That's one persons account.
I found improved results. YMMV.
mickcris wrote:I am only selling the boards as it is currently the best option available and Broken decided to stop selling them.
As mentioned before, the AVD has been available for a while now, just not listed on his shop.
mickcris wrote:I think situation with the PC Engine RGB is a bit different than something like the NESrgb where there was a definite difference between the old RGB mod and Tim's.
Apples and oranges? I can only speak to the performance of the two amp designs. The 2x gain from the THS7314 results in an overblown output. Adding 100 ohm resistors instead of 75 is a Band-Aid of sorts.
I've tried Tim's suggestion of using a voltage divider with the THS instead of just a higher value series resistor, but found that the AVD gives a better picture. I've tried the discreet transistor, NJM, THS, and AVD with the NEC systems and find that the AVD works the best.
mickcris wrote:I appreciate what Tim does, but to say that everyone else should just stop trying is silly.
Are you referring to this comment?
CkRtech wrote:In my opinion, the gaming community often thrives on trial and error with "well, it looks good to me… So that means the circuit must be acceptable."
IMHO improving the audio and video quality of retro gaming is an ongoing and evolving process. What was considered best 5 years ago may no longer be the case today! On the same token, is it not ok to evaluate and share the current state of what is available/possible? The THS was a great fit for mods that only needed a 2x gain (N64 RGB), and bypassing various RGB encoders, and still is for some applications. However, it was never quite right for the NEC systems (RGB levels too high, no CSYNC buffering, no audio buffering for TG16/PCE).
mickcris wrote:thesteve is an electrical engineer that came up with previous capacitor "fix" for the jailbars. It did not work on all consoles though. I think he actually had a thought process as to why he was doing it and was just not slapping capacitors everywhere till something worked.
Yes, he was on to something, but turns out he wasn't able to pin point the exact issue? Nobody's perfect!