Hello Joel Its probably worth trying the Czech company Krystaly – if you haven’t done so already. Their website is http://www.krystaly.cz/en/ I have previously obtained a small batch of crystals from

Hello Jared I’m sorry but I can’t remember all of the details from when I took the cavity apart – should have taken more photos. I’ve just taken the covers off and had another look at the PCB, but don

As far as I can remember it was fairly simple – as per the third photo in the album (the one with the red tape). The 50ohm resistor is soldered directly to the centre pin of the GR-874 and the two dio

Hello Jared I put some photos of the PCBs in the 2018 thread that Gudjon refers to – both sides of the PCB and the RF cavity. I had to replace the original mercury cells and a broken resistor where so

Yes, I once bought some crystals for an HP3456A from krystaly – I found them helpful and easy to deal with. Regards Kerry From: <TekScopes@groups.io> on behalf of Tam Hanna <tamhan@...> Rep

There was a DIY reflow PID controller published in the April/May 2020 Silicon Chip Magazine (https://www.siliconchip.com.au/Issue/Browse/Issues ). I haven’t tried building it, but it seems like a reas

I’ve also seen these striped transistors used in 1970s Revox audio equipment – probably occurred in other brands too. Kerry From: <TekScopes@groups.io> on behalf of <toby@...> Reply to

Hello Dennis Good to see this group is so well valued and supported. Just thought I should let you know that I couldn't see my $10 on the list - paypal transaction 5UE83392FH234861P dated 31 December.

Thank you Dennis. I made a small contribution yesterday - no problems with using paypal. Your efforts in administering this group are greatly appreciated. Although I make posts only rarely, the wealth

Hello All My SG503 front panel specifies a slightly different cable number - 012-0482-00 ( I do have one of these). Not sure how this differs from the 012-0480-00 but it does have a metal rather than

Thanks Dennis and Roger The Lecroy has a 'Random Interleaved Sampling' (RIS) mode for repetitive signals which I think may be similar to 'equivalent time sampling' on the Tek 2440. I tried the RIS mod

I'm embarrassed to say that the apparent problem with the SG504 seems to have more to do with operator error than any real fault. The Lecroy DSO being used to look at the SG504 output has only recentl

Hello Dennis I must admit I don't have a proper test setup - but to answer your specific questions (in reverse order): * I wonder if the problems you are experiencing are caused by using an ordinary c

Hello Craig I had a similar experience with the 067-0625-00. Put in the 1.5V batteries, but the unit wouldn't work. I found that the 50ohm input resistor was broken - probably because someone had remo

I have an SG504 which I'm trying to get working using a replacement levelling head from Ancel. The two reference frequencies (0.05 and 6Mhz) are both within spec. However, there are problems on both o

Hello Craig I've recently had to replace the original 1.35v mercury batteries in my 067-0625-00. I used 1.5v alkaline A1PX-BP1 batteries. Readily available and they are an exact fit - but you do need

Hello Petru I've put a couple of screenshots in the photos section (under TG501 5ns 2ns). The amplitude of the 5ns waveform is 1.24v pp and well within spec. The 2ns is 0.9v pp. this appears below spe

Hello Fabio i replaced U310 (with the help of another Tekscopes member) and this solved the problem. The 20ns, 10 ns and 5ns timing is now correct. I made most of the adjustments in the manual to maxi

Hello Fabio I've taken apart the TG501 and had a closer look. There are only three socketed chips - U310, U300 and U290. U310 is part of the first divide by 5 counter. I think the sockets are the dodg

Thank you Fabio. I'll have a closer look at the TG501 over the next few days - unfortunately its difficult to access any of the components on the main board without first removing the multiplier board