Jump to content
IGNORED

HRD 4000B


Ksarul

Recommended Posts

  • 3 weeks later...
  • 3 weeks later...

Four of the first six completed boards are already spoken for. I'm busy assembling eight more now. Answer here if you are still interested in purchasing one of the boards. The price is $185 plus $15 for a flat rate box to US addresses (somewhat more for postage to the rest of the world). The box can hold two assembled cards safely for those looking to purchase more than one card.

 

Bare boards are still $30 each, and include one 74HCT154 and six D7K diodes. One note on the diodes--check them with a meter so you are sure which end is which, as the truth is a bit counter-intuitive. The double white lines equate to the marked end of a US diode. . .not the single red line.

Edited by Ksarul
  • Like 6
Link to comment
Share on other sites

I really want to make a sidecar passthru one day so plug a PEB card like this into.

I’m thinking of a way around the regulator bypass issue. We can put a switch in new home brew PEB cards that would bypass the regulator and let you use an external PSU. When bypassed, plugging it in the PEB would just make it a dead card because it’s not getting any power from the external Jack. It wouldn’t blow anything. When not bypassed, it goes through the regulator like normal and the DC in Jack wouldn’t matter and be bypassed. We can even have standard instructions to adapt regular cards for this so folks could use them plugged into the sidecar passthru.

I’m sure the above idea has holes in it, but I’ve been mulling it over for a while.... :)

Link to comment
Share on other sites

A PEB Splitter will do exactly what yo want here: the sidecar peripherals are on one side and the PEB on the other. As long as you have no address conflicts between hardware on the sideport side and the PEB side, everything should work transparently. Note also that the Flex Cable Foot doesn't pass the 5V through in any event--IIRC, that line isn't connected there at all. Power to the buffer chips in it comes from the PEB, not the console.

  • Like 1
Link to comment
Share on other sites

On 5/23/2020 at 5:45 PM, acadiel said:

I really want to make a sidecar passthru one day so plug a PEB card like this into.

I’m thinking of a way around the regulator bypass issue. We can put a switch in new home brew PEB cards that would bypass the regulator and let you use an external PSU. When bypassed, plugging it in the PEB would just make it a dead card because it’s not getting any power from the external Jack. It wouldn’t blow anything. When not bypassed, it goes through the regulator like normal and the DC in Jack wouldn’t matter and be bypassed. We can even have standard instructions to adapt regular cards for this so folks could use them plugged into the sidecar passthru.

I’m sure the above idea has holes in it, but I’ve been mulling it over for a while.... :)

 

Slap some right angle header adapters on this : https://oshpark.com/shared_projects/0QDGf51I  and you can connect a PEB to my version of sideport nonsense... (female headers)   That's how I tested peb compatibility with the TIPI before designing the PEB board. 

 

Link to comment
Share on other sites

4 hours ago, speccery said:

I’d like to get the pare board (with the TTL chip and the diodes). I don’t have a PEB... so need to build something to go in between. What voltages does the board use?

It just uses the PEB's about 8V rail to feed a 5V regulator on the board. 

 

http://www.unige.ch/medecine/nouspikel/ti99/horizon.htm#Power supply

  • Like 1
Link to comment
Share on other sites

1 hour ago, INVISIBLE said:

Huh?  Getting this image was one of the simple ones, only requiring a simple LEFT CLICK & DRAG to the desktop.  Looks better rotated though...

 

 

 

...didn´t work for me. thx

(But "your" pic works)

Edited by Schmitzi
Link to comment
Share on other sites

@Schmitzi, I had issues with the picture too--it downloaded, but it would not open in a picture viewer afterward. I tried opening it with Paint--and it opened. It would not save a usable picture in JPG or PNG format, but it did save fine as a bitmap. I then saved the bitmap as a JPG or as a PNG, and those worked flawlessly. There must have been a malformed bit somewhere in the original picture that the process I followed cleared. . .

  • Like 2
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...