Yes, but this is NTSC-modulated VHF RF. Can current TVs receive that? I was under the impression that they don't. (I don't have one, no free time to waste) -Dave On 5/23/22 19:06, Dean Notarnicola via vcf-midatlantic wrote:
I’ve yet to find a TV that can’t do ATSC and NTSC.
On Mon, May 23, 2022 at 6:26 PM Glenn Roberts via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
I have no experience with Sinclair but didn’t they have a built-in RF modulator? That would put out an old style UHF or VHF signal that a modern digital TV can’t decode. I believe you’d need an older TV to test these…
Sent from my iPad
On May 23, 2022, at 5:54 PM, Dean Notarnicola via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
I’ve read that the ULA on some older TS and ZX units do not put out a 100% proper NTSC signal, something do with the contrast. It may be that modern TVs have issues, but CRT tuners can deal with it. Considering they are all demonstrating the same behavior, these units may be fine.
On Mon, May 23, 2022 at 4:32 PM Jeff S via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
The K cursor is normal, and standard. The ZX81 does not have any kind of intro or status boot screen. If you're seeing the K, then unless there's something wrong with the keyboard, you should be able to see any numbers you type.
On Mon, May 23, 2022, 4:21 PM Bob Shuster via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
So I have two (2) Sinclair ZX81s (US version - one is still an unbuilt kit), and three (3) Timex-Sinclair 1000s. I’ve connected them to a TV using an RCA-coax adapter and tuned to the correct channel, but I get a grey screen with the “K” cursor visible. I’m unable to get past this. This is for all four units. They seem to tune in white momentarily then switch to fuzzy grey - with the “K” still visible. This was both on a large 4K OLED set and a small HD LED TV, and I suspect they are just too new to deal with the monochrome signal. I don’t have a CRT TV to test with, just old monitors (which of course don’t have antenna connections.)
Any advice? I’m selling these, so I’m not getting into modding them, just want to confirm they’re working properly.
Bob Shuster
-- Dave McGuire, AK4HZ New Kensington, PA