Apple II

Apple II+ Composite Video issue

Hello, 

I have an Apple II+ with Video sync issues, 

Using a standard Apple composite monitor, I had vertical sync issues, and I changed a few ICs to fix it : 74LS161 x2 at D11 and D12, 74LS32 at C13 and 74LS32 at C14. 

Now the image is stable with the classic monitor. 

However when I use a Retrotink 2x pro, I do not get any sync (black screen). Using another Apple IIe I succeed with the retrotink. 

Is there any good document explaining step by step  to troubleshoot the apple II video sygnal using an Oscilloscope?

Where to start with ?

Thanks

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PAL IIe cassette interface

I'm having trouble sending audio files to the cassette interface in a IIe PAL version. There are clearly some ciruit changes e.g. no 741, but half an MC1458 opamp seems to be the zero crossing detector.  Is the basic format (frequencies 1kHz/2kHz/ 770Hz) the same, or were there slight differences due to the different clock crystals in these machines?  I guess I could adjust the speed of the recording wav file slightly.

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Unable to get serial started on IIe to use with ADTPro 2.1.0

I'm new to the forum and just pulled my IIe out after being in storage for a long time. I'm using ADTPro 2.1.0 to create some disks, but am having some trouble getting the serial working. When I enter IN#2 and press RETURN, I don't see the APPLE SSC: prompt. What I get is a bracket and then a random character after that.

Example: ]p

I verified that the card is in the second slot from the left as you look at the machine from the front, the dip switches are set to SW1: 1001111 SW2: 1101100, and the jumper block has the arrow pointing up since I'm using a null modem cable.

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RAM blocks architecture and total RAM amount

Hello, gentlemen!

 

I am devouring the masterpiece Understanding the Apple II by Mr. James Sather and the Apple II Reference Manual as well.

So far, so good, but I am stuck on the total amount of RAM available and considered by the system. I am aware that the 6502 processor can read/write 8 bits at a time (8 input/output lines) but has 16 lines available for dealing with addresses.

 

My issues are:

1) If I have 3 rows of 8 columns with a 16k chip at each socket, how can I have "only" 48k of RAM?;

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Case & power supply screws for //e

I have a couple of //e units that are missing one or more of the screws that attach the bottom plate of the machine to the top part of the case and/or the screws that attach the power supply to the base plate.  Does anyone know the specs of the screw types so I can order some?  Maybe a suggestion on the best place to order a few dozen of them or whatever the minimum package size is?

 

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Logical problem with Apple II europlus error and random freeze

I turned on my europlus today after a long time and I randomly find these errors, what could it be? Thank you

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simple //e cassette problem

First post!  So I'm sure I'm gonna break a bunch of rules!  :^)  I did search the forum for this question before posting!

 

This is my first foray into the // world.  I got a new-to-me //e.  I installed a ReActiveMicro PSU before even turning it on.

 

It didn't come with any DOS disks.  I've ordered some on eBay.  But in the meantime I tried writing a few lines of basic and SAVE'ing them to cassette.

 

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Saturn 128k Card testing without drives?

Hello, gentlemen!

After consulting Saturn 128k manual, this forum and other sources content I have the following question: is it possible to make a RAM/Card test at the 128k card without any input device where a program can run from?

I could not find any info about it and would really like to check if all the banks of my saturn card are working and if the 3 leds are ok as well.

Is it safe to run a CON command, as shown on reference manual, to set a memory state where the leds would light up, without any risk of changing anything permanently?

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"New" Apple II+: strange cable, strange behaviour

Hello, gentlemen!

Have already gathered a lot of info, checking this forum, but this is my first post.

 

Have just bought this nice Apple II+ on ebay. Seller shared a few nice pictures of everything working properly.

The package hit my place today and when I turn the Apple II+ on, the power light will not glow, just as will not the bulbs on some daughter boards (MicroModem and Saturn 128k ram). Motherboard beep is present.

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Where to get ANSITerm?

I purchased a WiFi Modem for my IIGS (this one https://tempestfpga.com/) but am looking for a copy of ANSITerm to use with it.

 

I've been able to use Spectrum to verify the modem works, but it seems ANSITerm works with ProDOS so it would be more convinient - i.e., don't have to wait for GS/OS to load and then Spectrum to load.I see it was for sale for a long while, even found ads for it from the early 2000's in Juiced.GS.  But I can't find any info about the company now - anyone know what happened or have current contact info?

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