HP 3310B Function generator - UK Vintage Radio Repair and Restoration Discussion Forum

govjohn · 4th Oct 2018, 12:13 pm

Hi, has anyone here had any experience with an HP 3310B function generator? I've got one as a shed find it looks very cute and its just what I want, but its faulty. As the tunnel diodes (which fortunately plug in) are OK I thought it would be worth repairing so I got the manual. A copy dated Oct 73 is widely available but its abysmal! The circuit diagrams are a joke. They are incomplete, don't join up different scales, randomly labelled and the voltages shown on the scrap of the output amplifier show it as being saturated. (attached) Surely HP manuals are better than this? After-all Tektronix manuals are a model of clarity. If any member of this forum has any experience/knowledge of this function generator in particular with regard to better documentation, could you let me know. Thanks , John.

orbanp1 · 4th Oct 2018, 2:32 pm

Hi John,

I do not have the above function generator, but here are my comments nonetheless:

- KO4BB has a good quality manual on its web site, it is 27MB:
http://www.ko4bb.com/getsimple/index..._3310AB_OS.pdf
You still need to paste together schematics pages, HP used to make beautiful quality manuals with "mile long foldouts", very usable in paper form. So it is the scanning, not the manual!

- Start by checking the power supply.

- I have not measured a tunnel diode yet, but I understand it can easily be destroyed by "regular" diode check measurements, it has a region where the characteristics have negative resistance, so be careful with them.
You really should measure them on a curve tracer.

Good luck, Peter

Radio Wrangler · 4th Oct 2018, 3:26 pm

Tunnel diode? In a low frequency function generator?

That's very unlikely.

David

dave cox · 4th Oct 2018, 3:56 pm

A1 has 2 tunnel diodes, CR21/22 (+/-5 level detector) and 2 hot carrier CR3/4
A3 has a couple of norton diodes, CR21/23
A5 has 3 hot carrier diodes, CR9/10/11

#### and a partridge in a pear tree ####

dc

factory · 4th Oct 2018, 5:59 pm

Quote:

Originally Posted by Radio Wrangler

Tunnel diode? In a low frequency function generator?

That's very unlikely.

David

Just had a look at some pictures of my A version and found one of the tunnel diodes, not sure where the other is hiding but it should be in there somewhere.

Click image for larger version

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I had trouble with the power supply in mine (Q20 was short circuit), I think the previous owner did too as it had been repaired before.
Also note that the power supply PCB has internal tracks (one of them had to be replaced with a link as a plated through-hole was damaged).

Looking at my pictures I have spotted a pair of Sprague type 109D wet tantalum capacitors, these are known to leak causing corrosion, so I will need to check & replace them at some point.

David

govjohn · 4th Oct 2018, 6:07 pm

orbanp1 Thanks for the reply, it appears to be an excellent quality down load and after I've stuck all the drawings together I should be able to sort it. As for testing the tunnel diodes I followed a video on U tube, search under Testing tunnel diodes, the video is by w2qew and its#204. This gives a good insight into how they work and they are really curious to play with. Thanks again for the download, John.

Chris55000 · 4th Oct 2018, 6:18 pm

Hi!

You have to take meticulous care with tunnel diodes, and an accidental test–prod slip or testing these incorrectly can easily destroy them!

The best thing I can suggest is to begin with all the power–supply voltages, then carry out a performance check to see exactly how much of this unit is operational, and what isn't.

You do need a good, reliable dual–beam oscilloscope and a high–quality DMM to fault–find this instrument – I'll download the manual and study it over the next day or two – keep us posted!

Chris Williams

Radio Wrangler · 4th Oct 2018, 8:06 pm

Tunnel diodes indeed! I didn't expect those in a lowish frequency func gen. Quite surprised.

I've used 3310s on lots of occasions but never had to go inside one. They just worked. I did have to do some re-design work on its great great grandson the 3325A when its frac-N synthesiser control chip went obsolete.

David

cmjones01 · 4th Oct 2018, 8:48 pm

Quote:

Originally Posted by Radio Wrangler

I've used 3310s on lots of occasions but never had to go inside one. They just worked. I did have to do some re-design work on its great great grandson the 3325A when its frac-N synthesiser control chip went obsolete.

Funny - without wishing to hijack the thread, I've just acquired a 3325B, and a fine (though rather large) instrument it is too. I doubt there are any tunnel diodes in there though!

It's nice to see its great-great-grandfather the 3310.

Chris

MrBungle · 4th Oct 2018, 9:56 pm

Always wanted a 3310. The mention of tunnel diodes has made me change my mind

4th Oct 2018, 12:13 pm	#1
govjohn Pentode Join Date: May 2011 Location: Cardigan, Ceredigion, UK. Posts: 100	HP 3310B Function generator Hi, has anyone here had any experience with an HP 3310B function generator? I've got one as a shed find it looks very cute and its just what I want, but its faulty. As the tunnel diodes (which fortunately plug in) are OK I thought it would be worth repairing so I got the manual. A copy dated Oct 73 is widely available but its abysmal! The circuit diagrams are a joke. They are incomplete, don't join up different scales, randomly labelled and the voltages shown on the scrap of the output amplifier show it as being saturated. (attached) Surely HP manuals are better than this? After-all Tektronix manuals are a model of clarity. If any member of this forum has any experience/knowledge of this function generator in particular with regard to better documentation, could you let me know. Thanks , John. Attached Thumbnails

4th Oct 2018, 3:26 pm	#3
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,876	Re: HP 3310B Function generator Tunnel diode? In a low frequency function generator? That's very unlikely. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

4th Oct 2018, 3:56 pm	#4
dave cox Nonode Join Date: Jan 2009 Location: Bristol, UK. Posts: 2,062	Re: HP 3310B Function generator A1 has 2 tunnel diodes, CR21/22 (+/-5 level detector) and 2 hot carrier CR3/4 A3 has a couple of norton diodes, CR21/23 A5 has 3 hot carrier diodes, CR9/10/11 #### and a partridge in a pear tree #### dc

4th Oct 2018, 6:07 pm	#6
govjohn Pentode Join Date: May 2011 Location: Cardigan, Ceredigion, UK. Posts: 100	Re: HP 3310B Function generator orbanp1 Thanks for the reply, it appears to be an excellent quality down load and after I've stuck all the drawings together I should be able to sort it. As for testing the tunnel diodes I followed a video on U tube, search under Testing tunnel diodes, the video is by w2qew and its#204. This gives a good insight into how they work and they are really curious to play with. Thanks again for the download, John.

4th Oct 2018, 6:18 pm	#7
Chris55000 Nonode Join Date: Aug 2007 Location: Walsall Wood, Aldridge, Walsall, UK. Posts: 2,870	Re: HP 3310B Function generator Hi! You have to take meticulous care with tunnel diodes, and an accidental test–prod slip or testing these incorrectly can easily destroy them! The best thing I can suggest is to begin with all the power–supply voltages, then carry out a performance check to see exactly how much of this unit is operational, and what isn't. You do need a good, reliable dual–beam oscilloscope and a high–quality DMM to fault–find this instrument – I'll download the manual and study it over the next day or two – keep us posted! Chris Williams __________________ It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!

4th Oct 2018, 2:32 pm	#2
orbanp1 Heptode Join Date: Nov 2009 Location: London, Ontario, Canada Posts: 675	Re: HP 3310B Funtion generator Hi John, I do not have the above function generator, but here are my comments nonetheless: - KO4BB has a good quality manual on its web site, it is 27MB: http://www.ko4bb.com/getsimple/index..._3310AB_OS.pdf You still need to paste together schematics pages, HP used to make beautiful quality manuals with "mile long foldouts", very usable in paper form. So it is the scanning, not the manual! - Start by checking the power supply. - I have not measured a tunnel diode yet, but I understand it can easily be destroyed by "regular" diode check measurements, it has a region where the characteristics have negative resistance, so be careful with them. You really should measure them on a curve tracer. Good luck, Peter

4th Oct 2018, 8:06 pm	#8
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,876	Re: HP 3310B Function generator Tunnel diodes indeed! I didn't expect those in a lowish frequency func gen. Quite surprised. I've used 3310s on lots of occasions but never had to go inside one. They just worked. I did have to do some re-design work on its great great grandson the 3325A when its frac-N synthesiser control chip went obsolete. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

4th Oct 2018, 9:56 pm	#10
MrBungle Dekatron Join Date: Jun 2016 Location: London, UK. Posts: 3,687	Re: HP 3310B Function generator Always wanted a 3310. The mention of tunnel diodes has made me change my mind