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1
Thanks for the ongoing efforts Chris, but it's unfortunately pretty much un-usable at the moment.  Constant timeouts and re-tries, took half an hour to write a 5-minute post.
2
I replaced all of the caps, I also replaced the Audio RCA connectors as well. Everything works perfectly, but I noticed an issue where the filter is always enabled on the right channel regardless of it being switched on or not (left channel still works as it should).

The filter circuit is simple enough.  Essentially switching it on/off puts either +12V or -12V on the gate terminal of both JFETs Q321 and Q331.  When the JFET is turned 'on', then audio bypasses the low pass filter formed by C332, C333, R332, R333.   See page 6 of the schematic:
http://amiga.serveftp.net/Schematics/A600_schematics/A600_R1-5_schematic.pdf

I'd suggest starting by confirming that you see +12V/-12V on the gate terminals of both JFETs when the filter is switched on/off.  https://www.amigapcb.org/ is useful to locate the parts and correct terminals.  If you're not seeing the +12V/-12V on one of the JFETs, then work backwards from there, you may find an open circuit track caused by corrosion damage.

If you are seeing +12V/-12V on the gate terminals, the right channel JFET (Q331) might be bad.  Replace it with the original MPF102, or a commonly available BFJ310 will work equally as well.

The left/right audio circuits are identical, so you can directly compare readings between them.  Amiga Test Kit has a handy function of generating a 10kHz tone to test the 4kHz low pass filter, and you can easily toggle the filter on and off.



I have looked at the rev 1.5 schematic and read somewhere that removing C331/C321 on the underside should bypass the filter but in this case doesn't seem to make any difference.

WTF, where did you read that garbage?  C331/C321 forms part of a fixed 27kHz low pass filter (by my calculation), and isn't part of the audio switch.

If you never want the 4kHz low pass filter to be enabled, and don't care about aliasing artefacts, then you can effectively disable the filter in multiple ways.  For example, linking the source and drain terminals of both JFETs would do this.  Or connect op-amp pins 5 to 8, and pins 3 to 14.  Or remove C322, C323, C332, C333.


Hope that helps.
3
These comprise of the full colour preview and excerpts of our Amiga Future issue 180 (May/June 2026) which can also be viewed online on the Amiga Future website.

ATTENTION. Issue 180 will be published approximately one week earlier than usual due to vacation.

Some of the interesting articles in this issue are:

Interview Carlo Perconti
Preview Kaboomania
Preview ARC4NERD
Review Roguecraft DX
Review farmiga
Review Ghosts’n Goblins AGA
Review Lüttje Bookholler 1.89
Review xSysInfo
Review Kyvos
Workshop Ambos

Of course there's actually so MUCH more in the magazine.

Needless to say you will often get other versions of software, some of which were commercially available, as well as some of the latest try-outs or freely released software applications and games for, hopefully, every Amiga variant of Operating system, so that's Amiga 'Classic', OS4, MorphOS, and AROS, including some PD software for these systems, all on the Readers' cover CD.

A detailed description of the varied content and excerpts of our current issue can be found at: https://www.amigafuture.de/app.php/kb/index?c=13

The Amiga Future magazine is available both as an English and German printed magazine - each issue is printed in FULL COLOUR - directly available from our magazine editorial office and from various other Amiga dealers.

Important Notice!

All our Amiga Future subscribers should check that both your current postal and email addresses for you are correct  that has been supplied by you to us.
The Amiga Future gets packed and shipped a few days prior to its actual release date. So, we need any change/correction to your address to be passed to us before we dispatch it, and in any case as soon as possible.
Bear in mind that: Usually requests to forward on mail will not be handled with such mail items, i.e. magazines!

We also ask that you check that your subscription fee(s) are current and up to date, i.e. already been paid, as some, in fact quite a few, subscription fees are still not currently fully paid.

Preview: https://www.amigafuture.de/app.php/kb/index?c=13
Orders: https://www.amigashop.org

http://40.amigafuture.de
https://www.amigafuture.de
http://www.apc-tcp.de
4
Amiga.org Discussion and Site Feedback / Site running slow and giving busy timeouts
« Last post by F0LLETT on April 10, 2026, 11:34:34 AM »
Hopefully this is solved.
The server has been the target of a constant DDOS attack. Specifically targetting our SQL DB.
I have taken steps to resolve this, so lets see how it goes.
5
A600GS & A1200NG / Re: Issue with my Amigakit Order
« Last post by X-death on April 10, 2026, 09:38:54 AM »
@F0LLETT

I’ve replied to your PM with my order details, thanks.
6
A600GS & A1200NG / Re: Issue with my Amigakit Order
« Last post by F0LLETT on April 10, 2026, 09:04:04 AM »
Not to hijack the thread, but can I chime in for an order placed last April?

Why post, just PM me.
7
A600GS & A1200NG / Re: Issue with my Amigakit Order
« Last post by Bradsco on April 10, 2026, 02:02:14 AM »
Not to hijack the thread, but can I chime in for an order placed last April?
8
Amiga Marketplace / A4000 060 ZZ9000 and USB For Sale Aberdeen Scotland £2000
« Last post by sheepz on April 09, 2026, 09:48:54 AM »
Hi

I have my A4000 060 ZZ9000 for sale on Amibay, its in Aberdeen Scotland and willing to do a deal with anyone that can collect.

Issues

Main issue is that if the video connector on the mother board other than the HDMI from the ZZ9000 is used the machine black screens and will not boot.

Other issue is the original floppy drive does not work very well.

It has been recapped in 2022 and a coin cell batter fitted after cleaning up the RTC area. Not perfect looking but I do have the RTC replacement kit from AmiBay to go with the computer.

Specs

CPU: A3660 from Amiga store - 39.21 MFlops no FPU

ROM: OS 3.2

RAM: 2 Mb CHIP RAM Plus GottaGo FaZt3r 256MB Z3 ram plus 256MB ram on the ZZ9000

Display: ZZ9000 graphics card

Sound: ZZ9000AX Amiga Audio Expansion

Keyboard: Amiga A2000 keyboard with adapter

Data Storage: CF card to expansion port on back

USB: Freeway PRO USB from 8 bit dreams AmiBay

Power Supply : PSU upgraded to Corsair SF600 600 Watt with cable adapter from a.mi.goun on AmiBay and frame from arymanx on AmiBay.

Will come with a A1200 mouse and A2000 Keyboard. Also, Original PSU, CPU card, CD drive face plate, internal HD brackets, Slot Covers, ROMs and 8MB Simms.

NOTE – Willing to post anywhere at buyers’ risk and expense but ideally pick up in Aberdeen Scotland.

Also included if wanted is boxes for the CPU, Graphics card, sound card and the badly painted LCD and speakers.
9
New User Introductions / Re: Reviving the Amiga Legacy—on SNES
« Last post by F0LLETT on April 08, 2026, 03:24:17 PM »
Looking good.
10
New User Introductions / Re: Reviving the Amiga Legacy—on SNES
« Last post by SUPER-J11BIT on April 08, 2026, 03:10:21 PM »
Mini Update: I Just Had to Show You This
https://drive.proton.me/urls/VVFRQQD1Y8#7o3xEZn32M61

Okay, I know.. I said the next post would be the official announcement of the finished game.
But I'm breaking that rule for a very good reason.

While working on the final level, I ended up putting together this armor hall.. and it turned out so good that there was no way I could keep it hidden until release. It instantly became one of my favorite rooms in the entire game.

So here it is: the armor hall from the last level.
Just a small preview, a little taste of the atmosphere you'll find in the finale. I won't spoil anything else, but trust me-its role in the game is pretty special.

Alright, now the next post will really be the final announcement.
We're almost there, and I can't wait for you all to play it.
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