Source for WD2793 Chips

[CheshireNoir]

Hi Folks,
Is there a reputable source of WD2793 FDD controllers that I can purchase from? I'd like to buy two, and getting them locally is a definite bonus. I'm wary of sourcing them from, say, AliExpress, unless someone has a store that consistently delivers good results :-)

Cheers!

Chesh

[ChickenMan]

I've got mine in the past from the US, sorry I'm on the way to Sydney so cant remember and dont have from whom with me.  Give me a week

[someone]

Someone can't help with a source of WD2793's but:

Someone's resorted to using the later industry standard WD3765 derivatives but these don't support odd floppy disk formats like the microbee.
31_WD37C65C.pdf (bitsavers.org)
The nice thing about the later versions is that they're buffered and can handle faster transfer rates.

From a jaded memory, the standard microbee can't handle the faster data transfer rates of the higher capacity disks unless the CPU frequency was boosted to 6MHz or more because doesn't use DMA thus uses software polling.

IDE Floppy disks, SuperFloppy, ZIP Drives & CDROMS, can also be used but it requires a substantial overhead to manage the ATAPI protocol overheads.

[CheshireNoir]

Thanks ChickenMan and someone,
I've taken a risk and ordered a few from China. Hoping they won't all be fakes.

Chesh

[CheshireNoir]

Related:
Anyone know where to source (Or suitable substitutes for) 74LS06, 74LS07 or HEF4511bp chips. (The latter I can source in SOIP so if I get really stuck I can probably bodge one in buuut...)

I'm sure these used to be a lot easier to get 2 years ago...

Cheers!

Chesh

[RedskullDC]

Is there a reputable source of WD2793 FDD controllers that I can purchase from? 

Hi Chesh, et al.

As someone said, there are other alternatives.

If you're not afraid to make an adapter board for the FDC chip, a WD1773 is a much superior option, and command compatible with the 1793/2793.

Contains a digital data separator, so you can dispense with most of the support circuitry the 2793 requires.
Most importantly, no more re-aligning it every couple of years!

https://www.ebay.com.au/sch/i.html?_from...nkw=WD1773

Regards,
Red

[ChickenMan]

"Anyone know where to source (Or suitable substitutes for) 74LS06, 74LS07 or HEF4511bp chips. (The latter I can source in SOIP so if I get really stuck I can probably bodge one in buuut...)
"
Mouser has them - https://au.mouser.com/c/?q=SN74LS06N

[CheshireNoir]

Thanks again, ChickenMan

As always, the Microbee community comes to my rescue :-)

Chesh

[someone]

"Anyone know where to source (Or suitable substitutes for) 74LS06, 74LS07 or HEF4511bp chips. (The latter I can source in SOIP so if I get really stuck I can probably bodge one in buuut...)
"
Mouser has them - https://au.mouser.com/c/?q=SN74LS06N

BTW - 7406 and 7407's would probably be suitable too.

What's the reason for the HEF4511? Are you driving a 7 segment LED?

Rather than using Mouser, Digikey, Element14, RS Components, XON and alike, Ewan or someone may have some of these ICs available.

---

Note: SN= prefix for TI, CD= prefix for NATSEMI/TI, HEF = prefix for PHILIPS/NXP

JAYCAR:
7406 DIP PACKAGE $2.95
7407 DIP PACKAGE $1.65
4511 DIP PACKAGE $1.95

ALTRONICS:
4511 DIP PACKAGE $1.75
(NO LONGER SEEMS TO STOCK 74 OR 74LS FAMILY)

Element14:
7406 DIP PACKAGE $2.05
7407 DIP PACKAGE $1.60
CD4511 DIP PACKAGE $1.29
74LS06 & 74LS07 DIP PACKAGE OUT OF STOCK ON BACK ORDER NOT DUE UNTIL 23/04/2022
(AROUND THE SAME PRICE)

[CheshireNoir]

HEF4511 was a typo. HEF4521 was what I believe I need (And there seems to be some uncertainty there) to put in IC39 spot on a certain 8342-3 Coreboard.

Chesh