开云体育

While going through another crate of Tektronix gear I came across this board, which has the legends "GPIB", "TEK T1", and "R-0291-XB". My google fu might be weak but I can't find any hint to the

Yes, solid state

By "diodes" do you mean solid state diodes (vs. tube diodes)? Thanks, Barry - N4BUQ

no the idea was to move them to a new location......hopefully they will be put to good use. Renée

A few other variants. Product Mod Description 453 120H Sawtooth out. 453 l27C Internal Sync Separator for TV applications. 453 l52J Special panel with "Property of Friden, Inc." lettering to be added

Guess I priced them too cheap!! That's GOOD. Cheap is GOOD!! They have been bought. Thanks!! -- Kim Herron W8ZV w8zv at goldenradioservice dot com www.goldenradioservice.com

Looking closer at the MOD703K doc, it shows diodes and not tubes. It appears the the MOD703H also has diodes on the HV assembly.

Thanks. I noticed the -A after I posted and could not correct it. CTR instead of CRT as well ;-) Looking at docs, it appears the the tubes were used in the later (20,000+) 453's as well. Now I am

All of the 453A (note that there is no hyphen in the model number) examples that I know of have solid state HV rectifiers in place of the pencil tube rectifiers, leaving the CRT as the only vacuum

Ray M <raymond.muno@...> added folder */Tek 453 variants*

I added the type study spreadsheet in the Files section. /g/TekScopes/files/Tek%20453%20variants/Tek%20453%20Type%20Study.xlsx

I the three Tek 453 scopes. Two are MOD703K, one is 703H. I find the docs that show some differences, along with changes. In the family, I find these variants 453 SN < 20,000 453 SN 20,000+ Major

I think that means a checksum failure. In other words, it’s detected that the data has corrupted in the non-volatile RAM. That’s typical of battery failure causing lost settings, but may happen if

Indeed, I found the SRAM datasheet, data retention is min. 2V. So I think with my Li battery still at 3.6V I am still OK. I checked the PS, especially the caps, none of them look bad, I will try to

Look to see what the lowest voltage is for data retention.? The 4.5 volts is the minimum for successful writing and reading. Data may be retained, but not manipulated, at lower voltages.? You see

"I don’t have a ‘megger’ or anything similar, so measuring leakage from the focus pot is not possible, other than with my DMM" Measure across each resistor in the series "chain" rather than

As Tom wrote data retention voltage can be lower than operating voltage. Sony datasheet specifies min data retention voltage as 2V. Ozan

An SRAM cell is a latch, and the voltage required to maintain the latching condition can be quite a bit lower than the value to read and write at datasheet speeds. A backup battery only needs to give

Adding to my above post: I am a bit puzzled because the Sony Sram requires min. 4.5v and the Li battery only supplies 3.45v to the Sram, how did that ever work ???

I think so, the battery model is ltc-16p-co-f-s2 from Keeper / 3,5v 1,6ah, a pretty big block and only a + and - connection. The Sram is Sony CXK58257P-12L where I measure 3.45v between gnd(14) &