Last days of the 172s on the electrified GOBLIN
 

On Thu, 25 Jan 2018 14:36:54 -0600
wrote:
In article
-september
..org, (Recliner) wrote:
By your logic, TfL should have ordered more of the proven, in-service
313s, not the dangerously new-fangled 378s, when increasing the LO fleet.

In fact, with modern manufacturing, especially where electronics are
involved, technology can move on to the point where obsolete design
manufacture is no longer affordable because the machinery is no longer
available.

This happened in the late 1990s with the radios used for RETB signalling.
Railtrack wanted more of an obsolete design of the radios which used a form
of electronics which was no longer makeable, more or less at any price. This

That sounds highly unlikely. You can still buy chips designed in the 70s
if you so desi

https://www.digikey.co.uk/catalog/en...roup/z80/15507

so the chances of whatever microcontroller the radios used being unavailable
is pretty slim. Plus the analogue radio components and op-amps will always be
available until someone invents usable optotronics. More than likely the cost
of redesigning the board for SMDs was more than railtrack was prepared to pay.

Last days of the 172s on the electrified GOBLIN
 

In message , at 09:47:43 on Fri, 26 Jan
2018, remarked:

You can still buy

a subset of

chips designed in the 70s if you so desi

Hence stories about NASA having to scour eBay for some parts need for
maintaining legacy equipment.
--
Roland Perry

Last days of the 172s on the electrified GOBLIN
 

In article , () wrote:

On Thu, 25 Jan 2018 14:36:54 -0600
wrote:
In article
-s
eptember.org, (Recliner) wrote:
By your logic, TfL should have ordered more of the proven, in-service
313s, not the dangerously new-fangled 378s, when increasing the LO
fleet.

In fact, with modern manufacturing, especially where electronics are
involved, technology can move on to the point where obsolete design
manufacture is no longer affordable because the machinery is no longer
available.

This happened in the late 1990s with the radios used for RETB signalling.
Railtrack wanted more of an obsolete design of the radios which used a
form of electronics which was no longer makeable, more or less at any
price.

That sounds highly unlikely. You can still buy chips designed in the
70s if you so desi

https://www.digikey.co.uk/catalog/en...roup/z80/15507

But you can't create the circuit boards and assemble them at affordable
costs. Repairing existing boards is another matter. There is an established
cottage industry that kept similar radios in use on the NRN until it was
switched off.

so the chances of whatever microcontroller the radios used being
unavailable is pretty slim. Plus the analogue radio components and op-amps
will always be available until someone invents usable optotronics. More
than likely the cost of redesigning the board for SMDs was more than
railtrack was prepared to pay.

So you know more than a multi-national radio manufacturing company? It's a
true story, as told to me by our salesman to Railtrack at the time.

The problem was the cost and time taken to get new technology-based radios
type approved for use in the small quantities needed for the areas of RETB
signalling.

--
Colin Rosenstiel

Last days of the 172s on the electrified GOBLIN
 

On Fri, 26 Jan 2018 12:02:51 +0000
Roland Perry wrote:
In message , at 09:47:43 on Fri, 26 Jan
2018, remarked:

You can still buy

a subset of

chips designed in the 70s if you so desi

Hence stories about NASA having to scour eBay for some parts need for
maintaining legacy equipment.

NASA tends not to use off the shelf parts.

Last days of the 172s on the electrified GOBLIN
 

On Fri, 26 Jan 2018 06:32:11 -0600
wrote:
In article , () wrote:
That sounds highly unlikely. You can still buy chips designed in the
70s if you so desi

https://www.digikey.co.uk/catalog/en...roup/z80/15507

But you can't create the circuit boards and assemble them at affordable
costs.

Which is what I said.

so the chances of whatever microcontroller the radios used being
unavailable is pretty slim. Plus the analogue radio components and op-amps
will always be available until someone invents usable optotronics. More
than likely the cost of redesigning the board for SMDs was more than
railtrack was prepared to pay.

So you know more than a multi-national radio manufacturing company? It's a
true story, as told to me by our salesman to Railtrack at the time.

Told to you by a salesman? Oh well, it MUST be true then.

Last days of the 172s on the electrified GOBLIN
 

In message , at 14:22:42 on Fri, 26 Jan
2018, remarked:

You can still buy

a subset of

chips designed in the 70s if you so desi

Hence stories about NASA having to scour eBay for some parts need for
maintaining legacy equipment.

NASA tends not to use off the shelf parts.

The ones in question are, otherwise they'd not be on eBay [as a result
of someone breaking up some old equipment and selling whatever they can
dis-assemble as spares].

Often they are things as boring as specific versions of a generic
processor or memory chip, which come in thousands of different variants.
--
Roland Perry

Last days of the 172s on the electrified GOBLIN
 

On Fri, 26 Jan 2018 14:46:42 +0000
Roland Perry wrote:
In message , at 14:22:42 on Fri, 26 Jan
2018, remarked:

You can still buy

a subset of

chips designed in the 70s if you so desi

Hence stories about NASA having to scour eBay for some parts need for
maintaining legacy equipment.

NASA tends not to use off the shelf parts.

The ones in question are, otherwise they'd not be on eBay [as a result
of someone breaking up some old equipment and selling whatever they can
dis-assemble as spares].

Often they are things as boring as specific versions of a generic
processor or memory chip, which come in thousands of different variants.

Be that as it may, I doubt a GPRS radio used such obscure parts that they
were unavailable a decade later.

Last days of the 172s on the electrified GOBLIN
 

In message , at 15:34:23 on Fri, 26 Jan
2018, remarked:
You can still buy

a subset of

chips designed in the 70s if you so desi

Hence stories about NASA having to scour eBay for some parts need for
maintaining legacy equipment.

NASA tends not to use off the shelf parts.

The ones in question are, otherwise they'd not be on eBay [as a result
of someone breaking up some old equipment and selling whatever they can
dis-assemble as spares].

Often they are things as boring as specific versions of a generic
processor or memory chip, which come in thousands of different variants.

Be that as it may, I doubt a GPRS radio used such obscure parts that they
were unavailable a decade later.

Everyone familiar with the specific project has told you otherwise.
--
Roland Perry

Last days of the 172s on the electrified GOBLIN
 

In article , (Roland Perry)
wrote:

In message , at 15:34:23 on Fri, 26 Jan
2018, remarked:
You can still buy

a subset of

chips designed in the 70s if you so desi

Hence stories about NASA having to scour eBay for some parts need for
maintaining legacy equipment.

NASA tends not to use off the shelf parts.

The ones in question are, otherwise they'd not be on eBay [as a result
of someone breaking up some old equipment and selling whatever they can
dis-assemble as spares].

Often they are things as boring as specific versions of a generic
processor or memory chip, which come in thousands of different
variants.

Be that as it may, I doubt a GPRS radio used such obscure parts that they
were unavailable a decade later.

Everyone familiar with the specific project has told you otherwise.

The RETB radios weren't GPRS for a start.

--
Colin Rosenstiel

Last days of the 172s on the electrified GOBLIN
 

In article , () wrote:

On Fri, 26 Jan 2018 06:32:11 -0600
wrote:
In article , () wrote:
That sounds highly unlikely. You can still buy chips designed in the
70s if you so desi

https://www.digikey.co.uk/catalog/en...roup/z80/15507

But you can't create the circuit boards and assemble them at affordable
costs.

Which is what I said.

so the chances of whatever microcontroller the radios used being
unavailable is pretty slim. Plus the analogue radio components and
op-amps will always be available until someone invents usable
optotronics. More than likely the cost of redesigning the board for
SMDs was more than railtrack was prepared to pay.

So you know more than a multi-national radio manufacturing company? It's
a true story, as told to me by our salesman to Railtrack at the time.

Told to you by a salesman? Oh well, it MUST be true then.

He was an engineer who maintained the company's relationship with the
railway. We made all the NRN radios in the 1980s and 1990s (at least all
those I've seen in cabs on depot visits in recent years). I worked there for
over 25 years so knew a lot about how the kit was manufactured.

--
Colin Rosenstiel