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Philips210 · 24th Mar 2018, 3:08 pm

Hugo

The Tank project sounds very good and it would be great to see some pics as it is being built. Talking of TTL ICs, I have found a couple of 7489 ics in my stock of parts and I was surprised to learn they're actually 64 Bit RAM devices, I was unaware these were part of the TTL family. We tend to think of gates, counters, flip-flops, registers etc but not memory.

Are the PCBs of the plated through hole type? I've found desoldering the ics on this type of board calls for considerable care to avoid damaging the copper foil pads. I remember being told a long time back it's often better to apply a small amount of fresh solder to each joint to assist when using the desoldering braid. It helps the solder to flow better. I like the reliable turned pin IC sockets, although pricey are worth using when building from scratch to prevent any possible damage to the board.

Regards
Symon

24th Mar 2018, 3:08 pm	#35
Philips210 Nonode Join Date: May 2007 Location: Redruth, Cornwall, UK. Posts: 2,579	Re: Interpreting a hexdump table Hugo The Tank project sounds very good and it would be great to see some pics as it is being built. Talking of TTL ICs, I have found a couple of 7489 ics in my stock of parts and I was surprised to learn they're actually 64 Bit RAM devices, I was unaware these were part of the TTL family. We tend to think of gates, counters, flip-flops, registers etc but not memory. Are the PCBs of the plated through hole type? I've found desoldering the ics on this type of board calls for considerable care to avoid damaging the copper foil pads. I remember being told a long time back it's often better to apply a small amount of fresh solder to each joint to assist when using the desoldering braid. It helps the solder to flow better. I like the reliable turned pin IC sockets, although pricey are worth using when building from scratch to prevent any possible damage to the board. Regards Symon