HP Pulse Generator type 1900A - UK Vintage Radio Repair and Restoration Discussion Forum

Nymrod121 · 23rd Mar 2018, 12:20 pm

As received (albeit after the covers/screening removed).

I like the overall build quality - and the air-handling arrangement is impressive as well.

Interesting colour scheme - I wonder if this was a 'U.S. Navy' (or 'UK RAF') specified item ... David (Radio Wrangler) - any ideas/thoughts?

G.

(mods: please relocate this post if/as you think fit)

cmjones01 · 23rd Mar 2018, 12:25 pm

That's a nice piece of kit. It's the same size and shape as my 5245L counter, I think. The greyish-blue colour of the panels looks the same, too, so I think it's just HP standard of the era rather than a special for the RAF.

Chris

Radio Wrangler · 23rd Mar 2018, 12:29 pm

The colour was HP corporate standard for the era. The cabinet castings, lids, sides are called System-I. If you bought HP gear, you got that colour.

The later cabinet System-II went metric and was a lot more modular (it's the one you can never find feet for) and then the colour scheme switched to what was affectionally known as duck s**t green.

David

Nymrod121 · 23rd Mar 2018, 10:44 pm

I have a spare foot for each of my '8640B and '436A (both of which are in D.S. green

)
G.

Radio Wrangler · 24th Mar 2018, 12:33 am

The one on the left is a system II foot, presumably photographed just before it fell off into a hyperspatial worm-hole

The one on the right is the far better system I foot with a metal button and spring for positive retention.

David

Argus25 · 24th Mar 2018, 1:23 am

It is really nice to see laboratory equipment that has been so well made.

Nymrod121 · 26th Mar 2018, 11:10 am

Agree with you 100% on that one

Only problem I've found with the System 1 type is that the bottom casing panel's 'foot-slots' tend to get distorted and removal for maintenance can be troublesome.

I came across an HP System 1-cased item recently where the spring-loaded rivet was visibly bent over, no doubt due to the determined attention of a burly (and clearly very frustrated) maintenance technician.

factory · 26th Mar 2018, 7:57 pm

Quote:

Originally Posted by Radio Wrangler

The colour was HP corporate standard for the era. The cabinet castings, lids, sides are called System-I. If you bought HP gear, you got that colour.

The later cabinet System-II went metric and was a lot more modular (it's the one you can never find feet for) and then the colour scheme switched to what was affectionally known as duck s**t green.

The later System-1 cases also came in DS green (I have a few here), they also seemed to stop engraving the front panel legends, as well as updating the mains input connector to the IEC type & changing the mains indicator lens to clear for the neon (was red).

David

Radio Wrangler · 26th Mar 2018, 10:43 pm

Yep, there was an overlap with some products that never got redesigned when the corporate colour edict changed. EG the 8640

The silk screened front panel used 2-pack paint and inks, so the lettering epoxy-bonds to the paint.

David

Nymrod121 · 27th Mar 2018, 8:18 am

Today, I shall be doing a careful power-up (via variac to give long-hibernated electrolytics a chance to wake up gently). More anon ...

Guy

Nymrod121 · 27th Mar 2018, 11:30 am

Getting there ... it's on a rolling simmer at the moment

Reading through the Ops & Svc manual, I came across a reference to a blue/gray color scheme offered as 'Option X95' - see pic.

G.

23rd Mar 2018, 12:20 pm	#1
Nymrod121 Nonode Join Date: Apr 2012 Location: Worcestershire, UK. Posts: 2,052	HP Pulse Generator type 1900A As received (albeit after the covers/screening removed). I like the overall build quality - and the air-handling arrangement is impressive as well. Interesting colour scheme - I wonder if this was a 'U.S. Navy' (or 'UK RAF') specified item ... David (Radio Wrangler) - any ideas/thoughts? G. (mods: please relocate this post if/as you think fit) Attached Thumbnails __________________ "What a depressingly stupid machine." [Marvin: HHGTTG] Last edited by Nymrod121; 23rd Mar 2018 at 12:26 pm. Reason: formatting

23rd Mar 2018, 12:25 pm	#2
cmjones01 Nonode Join Date: Oct 2008 Location: Warsaw, Poland and Cambridge, UK Posts: 2,681	Re: American-style mains input connector That's a nice piece of kit. It's the same size and shape as my 5245L counter, I think. The greyish-blue colour of the panels looks the same, too, so I think it's just HP standard of the era rather than a special for the RAF. Chris __________________ What's going on in the workshop? http://martin-jones.com/

23rd Mar 2018, 12:29 pm	#3
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,902	Re: American-style mains input connector The colour was HP corporate standard for the era. The cabinet castings, lids, sides are called System-I. If you bought HP gear, you got that colour. The later cabinet System-II went metric and was a lot more modular (it's the one you can never find feet for) and then the colour scheme switched to what was affectionally known as duck s**t green. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

23rd Mar 2018, 10:44 pm	#4
Nymrod121 Nonode Join Date: Apr 2012 Location: Worcestershire, UK. Posts: 2,052	Re: HP Pulse Generator type 1900A I have a spare foot for each of my '8640B and '436A (both of which are in D.S. green ) G. Attached Thumbnails __________________ "What a depressingly stupid machine." [Marvin: HHGTTG]

24th Mar 2018, 12:33 am	#5
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,902	Re: HP Pulse Generator type 1900A The one on the left is a system II foot, presumably photographed just before it fell off into a hyperspatial worm-hole The one on the right is the far better system I foot with a metal button and spring for positive retention. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

24th Mar 2018, 1:23 am	#6
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: HP Pulse Generator type 1900A It is really nice to see laboratory equipment that has been so well made.

26th Mar 2018, 11:10 am	#7
Nymrod121 Nonode Join Date: Apr 2012 Location: Worcestershire, UK. Posts: 2,052	Re: HP Pulse Generator type 1900A Agree with you 100% on that one Only problem I've found with the System 1 type is that the bottom casing panel's 'foot-slots' tend to get distorted and removal for maintenance can be troublesome. I came across an HP System 1-cased item recently where the spring-loaded rivet was visibly bent over, no doubt due to the determined attention of a burly (and clearly very frustrated) maintenance technician.

26th Mar 2018, 10:43 pm	#9
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,902	Re: HP Pulse Generator type 1900A Yep, there was an overlap with some products that never got redesigned when the corporate colour edict changed. EG the 8640 The silk screened front panel used 2-pack paint and inks, so the lettering epoxy-bonds to the paint. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

27th Mar 2018, 8:18 am	#10
Nymrod121 Nonode Join Date: Apr 2012 Location: Worcestershire, UK. Posts: 2,052	Re: HP Pulse Generator type 1900A Today, I shall be doing a careful power-up (via variac to give long-hibernated electrolytics a chance to wake up gently). More anon ... Guy __________________ "What a depressingly stupid machine." [Marvin: HHGTTG]

27th Mar 2018, 11:30 am	#11
Nymrod121 Nonode Join Date: Apr 2012 Location: Worcestershire, UK. Posts: 2,052	Re: HP Pulse Generator type 1900A Getting there ... it's on a rolling simmer at the moment Reading through the Ops & Svc manual, I came across a reference to a blue/gray color scheme offered as 'Option X95' - see pic. G. Attached Thumbnails