Re: CDV-700 Transformer Tester and other essential shop-made service tools

#701

Testing done on the first of these, haven't found the 4 wire/2 wire one yet, but hey, I cleaned up my bench over the weekend, I can't find anything!

ENi transformer on the Octopus transformer tester- perfect in all respects. Producing way more HV to turn on the Zedner regulator I added to the tester this morning at 908V DC.

Color wire transformer- here's where the Octopus come in handy. We can guess the pairs of winding by using an Ohmmeter, to check their DCD resistance, one is normally 5 Ohms, the other more but not a lot, but enough to identify, and the HV one is always way higher than the other two. What we don't know is the polarity of each winding. These HV generators nee the polarity just right on all 3 windings or nada. Try that with a power transformer, you get an explosion! Once I got the polarities all in line this transformer also produced HV output, but below the level required to activate the Zeners. By reading it's in the 850V range. Probably good for most GC work, but we really need the regulator online to get the best performance. This is at 3V. I can and will try higher, but that's not the point, I think.

Next I'll scare up the 4/2 wire job.

Geo

Re: CDV-700/ Geiger Counter Home Shop, or: A day in the life, down and dirty

#700
Edited

Chapter 2:? The Leaning Curve?

Initially the plan was to gobble up one or 2 examples of each version of the CDV-700 as well as many different vintage commercial Geiger counters, and their manuals, which were used as a study guide to get ideas what was needed, what wasn't needed, what could and couldn't be done, etc.

The first attempt to customize a CDV-700 was on a Victoreen CDV-700, which I called the updated version a
"Victory 7000" , then "CDV-7000" because in my mind it was 10X better than the original '700.

As you can see, seeds of the LENi we taking shape already. BNC connector on the panel, BNC on the probe, battery box changeout and a first step for sound, this one was a SonAlert driver boar, ideas already installed for Red "Count "LED(one flash p[er click)?, and green power LED, Fast-Slow response switch (fast fopr fast clicks, slow for slow clicks- makes reading more accurate by averaging over a few seconds, or more), and Reset button, for when you go off scale and want to dump the averaging capacitor- all features found on different high end commercial GC's, but not all in one instrument really.
Geo

CDV probe BNC adaption.jpg

CDV probe BNC adaption.jpg

Victory 7000 insides.jpg

CDV-700/ Geiger Counter Home Shop, or: A day in the life, down and dirty

#699
Edited

Chapter 1)

Hard to believe 20 years went by since the US Gov't started scrapping CDV-700s.

A few passed through my shop.

Most were ENi's (Electro Neutronics inc." the last versions, CDV-700 6B. built around 1964.

They came in original Civil Defense individual boxes, within a larger shipping box or crate of 10, most even still had the original black and white stripped carbon D cells, made by Burgess. I can't remember how many of those long dead dry cells I stripped for their Zinc cans and carbon rod element. for projects (and much later for Zn and Mn element XRF calibration targets).

Most of these were headed to scrap dumps, when some were gobbled up by early Junkers/sellers on eBay. One fellow in Alabama I think,?had a warehouse full, and wanted to empty the warehouse for other storage. I was glad to oblige and helped the poor fellow out. We would get regular shipments or 5 or 10 crates, once in a while 20 crates, each crate with 10 gleaming as-new ENi CDV-700, individually boxed with all accessories and manuals (2 each box!).

Back in those days, eBay did not allow pictures on their site, but you could post a link to pictures, which was rather a difficult prospect at the time, as anyone who would host them for you charged an arm and a leg. Remember 28k dial up modems? Anyone else remember when eBay was all text? Description's ran into the pages. I remember watching the originator being interviewed by the Business Channel host that I watched by satellite in 1998, and they ripped him up pretty good, basically saying it wouldn't work!

In those days, my hobbies were Ham Radio, Electronics, Machine Shop, and Microscopes. In 1991 (correction- 2001) when the first plane hit I got out of the stock market before the second plane hit, and went full bore Geiger Counters. Thankfully Tom Harmon had the CDV700CLUB up and running, that was a great help getting started.?

With all these Geiger Counters lying around, it occurred to me that they could be modified into more interesting instruments. This did not sit well with some members of CDV700Club, saying they should be left pristine, warts and all.

So around 1993 I started my own brand of GC group called GeigerCounterEnthusiasts@YahooGroups. At it's peak we had 2000+ members and it was the most popular Yahoo Group in the "Physics" category, and it was private not public.. By the time we ran out of Yahoo memory, there were 50,000 posts on the "first page" as it wound up being. The PAGE-2 version and others followed, with specialty groups for Gamma Spectrometry and later XRF.

ENistorage1.jpg

ENistorage2.jpg

ENistorage3.jpg

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#698

开云体育

Nice work, Geo!

I thought of making a similar test jig myself but time is a rare commodity these days.?

Well done!

AlanJ

Show quoted text

On May 23, 2022, at 11:43 PM, Michael C <mtcooper01@...> wrote:

the 3 wire each side was the original on the ENi.?

the transformer on the board with the multicolored wires I got from Lenox 2 years ago.?

the other transformer 4 wires one side 2 the other, bought off ebay "flyback transformer".? ?

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#697

the 3 wire each side was the original on the ENi.?

the transformer on the board with the multicolored wires I got from Lenox 2 years ago.?

the other transformer 4 wires one side 2 the other, bought off ebay "flyback transformer".? ?

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#696

Where did those come from Michael?

You mentioned before but I forgot.

Geo

Show quoted text

From: "Michael" <mtcooper01@...>
To: "CDV700CLUB" <[email protected]>
Sent: Monday, May 23, 2022 10:28:12 PM
Subject: Re: [CDV700CLUB] CDV-700 Transformer Tester and other essential shop-made service tools

hey George, that is cool.? ?Glad the transformer is working.? Actually helps me knowing that - hone my trouble shooting skills and focus more on the other parts of the circuit.? ?and I want to understand more about transformers especially multiple windings.??

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#695

hey George, that is cool.? ?Glad the transformer is working.? Actually helps me knowing that - hone my trouble shooting skills and focus more on the other parts of the circuit.? ?and I want to understand more about transformers especially multiple windings.??

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#694

开云体育

Hi Geo,

? This is an interesting coincidence you bring this up at this time.? I was using my cheap Mulitifunction tester-TC1 (available for less than $20 with free shipping on eBay) to test some transistors.? For those that may not have not seem my earlier post, they determine the type of part, display a schematic symbol allowing you to determine what pin is what, and display measurements of the parameters it chooses for the part identified.? Pretty cool for a <$20 instrument.? The downside is you have no idea how it performs the determination and test and sometimes that is important.

? The transistors I am testing were made available by one of the Geiger groups members a few years back.? They are Black Philco 2N1499A PNP Germanium transistors, I have 15 of them.? The date codes is 6237 on all of them so they are pretty close to 60 years old.? I tested them with the TC1 with an interesting and puzzling result.? They all were determined by the unit to be transistors (ie: no failed parts).? However, 7 of them came up with an alternate component symbol that is a PNP transistor with a C-E connected “damper” diode (Anode to C, cathode to E).? I had never run into that discrepancy before, but have mostly tested silicon transistors.? The diode detection seemed repeatable but there does seem to be something that can change it, it looks like it is DUT temperature.?

??Below is a list of the data for the parts per my TC1.? I noticed a substantial change in Iceo (ie: leakage) between the first and subsequent tests on some of the devices so I ran the test 10 times and recorded the data again.? I thought Iceo may be increasing as the die temp goes up for each test, but the data doesn’t seem to reflect that.? I would have to do more testing and I don’t want to do that right now.? Another anomaly is that ?on some parts it displays Ices- the collector to emitter leakage with base shorted to emitter.? Since there is no way to know what would enable/disable testing that parameter, it is a mystery.? The different collector currents (Ic) are interesting as well.

? This isn’t very useful because I thought I could get some info from the Lectrotech, but that didn’t work out.? If you have some of these transistors it might be interesting to see it.

?

- Means the tester did not test the parameter.

(10) is the data after 10 tests were completed.? Data for #1 - #3 was run after all other data was entered since I didn’t catch the changes until #4.

?

Trans# hfe???????? Vbe(mV)???????????? Ic(mA)? Iceo(uA)????????????? Ices(uA)?????????????? diode

1????????????? 159???????? 222???????????????????????? 1.6????????? 37?????????????????????????? -????????????? ??????????????? no

1 (10)???? 170???????? 223???????????????????????? 1.8????????? 61?????????????????????????? -????????????????????????????? no

2????????????? 84?????????? 292???????????????????????? 6.6????????? 14?????????????????????????? -????????????? ??????????????? no

2 (10)???? 78?????????? 286???????????????????????? 6.6????????? 8????????????????????????????????????????????????????????????? no

3????????????? 182???????? 210???????????????????????? 1.9????????? 80?????????? ??????????????? -????????????? ??????????????? no

3 (10)???? 160???????? 209???????? ??????????????? 1.7????????? 69?????????????????????????? -????????????? ??????????????? no

4????????????? 221???????? 204???????? ??????????????? 2.3????????? 100???????? ??????????????? -????????????? ??????????????? no??????????

4 (10)???? 201???????? 209???????????????????????? 2.1????????? 58?????????????????????????? ??????????????? -????????????? ??????????????? no?????????? Noticed leakage drops between subsequent tests????????????

5????????????? 77?????????? 272???????????????????????? 6.6????????? 8????????????? ??????????????? -????????????? ??????????????? no

5 (10)???? 75?????????? 277???????? ??????????????? 6.6????????? 5????????????????????????????? -????????????? ??????????????? no

6????????????? 166???????? 223???????????????????????? 1.7????????? 120???????????????????????? -????????????? ??????????????? no

6 (10)???? 153???????? 223???????? ??????????????? 1.6????????? 68?????????????????????????? -????????????? ??????????????? no

7????????????? 48?????????? 255???????? ??????????????? 6.6????????? 50?????????? ??????????????? 17?????????? ??????????????? no

7 (10)???? 46?????????? 265???????????????????????? 6.6????????? 32?????????? ??????????????? 14?????????? ??????????????? no?????????? 1st time Ices showed up on tester

8????????????? 69?????????? 288???????? ??????????????? 6.6????????? 14?????????????????????????? -????????????? ??????????????? 4.31V

8 (10)???? 72?????????? 298???????? ??????????????? 6.6????????? 7????????????????????????????? -????????????????????????????? 4.4V? ???? Heated the part and Iceo increased to 120 and Ices showed up at 4.? Iceo goes up with increases in temp.

9????????????? 38?????????? 282???????? ??????????????? 6.5????????? 10?????????????????????????? -????????????????????????????? no

9 (10)???? 37?????????? 282???????? ??????????????? 6.5????????? 7????????????? ??????????????? -????????????????????????????? no

10?????????? 51?????????? 284???????? ??????????????? 6.6????????? 7????????????????????????????? -????????????????????????????? 4.18V

10 (10)? 49?????????? 287???????? ??????????????? 6.5????????? 4????????????? ??????????????? -????????????????????????????? 4.26V

11?????????? 54?????????? 269???????????????????????? 6.6????????? 21?????????????????????????? -????????????????????????????? 4.41V

11 (10)? 52?????????? 275???????? ??????????????? 6.6????????? 12?????????????????????????? -????????????????????????????? 4.4V

12?????????? 465???????? 223???????? ??????????????? 5.7????????? 920???????? ??????????????? 1????????????????????????????? no? ???????? This tested as having the diode earlier.

12 (10)? 488???????? 229???????????????????????? 5.6????????? 780???????????????????????? -????????????????????????????? no??????????

13?????????? 76?????????? 278???????? ??????????????? 6.6????????? 8????????????????????????????? -????????????????????????????? 4.05V

13 (10)? 71?????????? 281???????????????????????? 6.6????????? 5????????????????????????????? -????????????????????????????? 4.07V

14? ???????? 40?????????? 267???????? ??????????????? 6.5????????? 8????????????????????????????? -????????????????????????????? 4.19V

14 (10)? 36?????????? 282???????????????????????? 6.5????????? 2????????????? ??????????????? -????????????????????????????? 4.19V

15?????????? 27?????????? 298???????????????????????? 6.4????????? 1????????????????????????????? -????????????????????????????? 4.24V

15 (10)? 24?????????? 304???????????????????????? 6.4????????? -????????????????????????????? -????????????????????????????? 4.28V

?

My conclusion at this time is the TC1 is okay as a transistor tester but without a known good tester to compare it to it I can’t determine the accuracy of the hfe measurements.? They seem

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#693

This evening's project added the next important tester I call the "Octopus" (see if you can figure out why?)

It's a straight clone of the ENi on my version of perfboard.

There are 6 wires with clips on the end, corresponding to the 6 terminals on Eni etc. transformers. With it I can now test ENi etc. HV transformers without endangering a CDV700 board at all. It uses the Russian transistor, the first time I ever used one.

Note to Michael C- the first one tested was one you sent me with 3 wires on each side, it works well. As a matter of fact, it was putting out 900V even with the input DC turned down to 1V, and only drawing 30mA to boot,

Pics of the beast attached.

Geo

PS it took longer than expected, I had some of that one band high wattage resistors in backwards.

Flying transformer tested.jpg

Flying transformer tested.jpg

Still-Working_at_1V.jpg

30mA_at_1V_in_916V_out_amazing.jpg

Used_to_Test-Primary_side_Zener_regulator.jpg

916V_on_Ludlum_500_1V_in_at_30mA.jpg

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#692

开云体育

It’s line powered.? It’s in decent shape, I am going to have to open it up and take a look.

?

Clay

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Geo Dowell
Sent: Monday, May 23, 2022 7:02 PM
To: CDV700CLUB
Subject: Re: [CDV700CLUB] CDV-700 Transformer Tester and other essential shop-made service tools

?

That looks like a real winner Clay! What is the battery compliment inside or does it have AC power, fporgot to look?

?

I just finished building a transformer tester with a Russian transistor, and it will do 900V @1V and 30 mA, yes interesting devices. Their low forward drop should have some definite advantages in some area??

?

Will be post picks of the "Octopus" shortly.

?

Geo

?

From: "freshndaire" <fanman@...>
To: "CDV700CLUB" <[email protected]>
Sent: Monday, May 23, 2022 5:55:23 PM
Subject: Re: [CDV700CLUB] CDV-700 Transformer Tester and other essential shop-made service tools

?

Does anyone here have a manual for a Lectrotech Model TT-250 In-Circuit Transistor Analyzer?? I have one that seems to have issues, and do not understand how it is supposed to be used.? I have had no luck finding a manual or schematic.? Even finding someone that has a working one and/or knows how to use it properly would be good.? Here’s the most info I have found on it: ?? There are picture on eBay of one or more of them.? It does transistors and diodes.? Mine seems to have auto-biasing issues, and the leakage currents may be inaccurate.? High and low Beta ranges don’t line up well.? The in-circuit test mode seems to have problems due to switches that need to be cleaned, but does work for Beta Checks.? I will have to tear into it at some point, but it wasn’t a cheap tester in its day so I’d like to get it tuned up and 100% working as it seems to have a lot of potential.

I have been testing some Germanium transistors and getting “interesting” results with my Multi-Function Tester-TC1.? I’ll post the data after I get it all entered.

?

Clay Scott

?

From: [email protected] [mailto:[email protected]] On Behalf Of peter via groups.io
Sent: Monday, May 23, 2022 2:20 PM
To: [email protected]
Subject: Re: [CDV700CLUB] CDV-700 Transformer Tester and other essential shop-made service tools

?

geo

i have the same heathkit tr checker
it just a different colour. i got mine for $1 at ham club swap meet. i also have a radio shack tr tester that uses the transistor in an oscillator to light a neon bulb. it gives a crude relative gain estimate

p

?

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#691

That looks like a real winner Clay! What is the battery compliment inside or does it have AC power, fporgot to look?

I just finished building a transformer tester with a Russian transistor, and it will do 900V @1V and 30 mA, yes interesting devices. Their low forward drop should have some definite advantages in some area??

Will be post picks of the "Octopus" shortly.

Geo

Show quoted text

From: "freshndaire" <fanman@...>
To: "CDV700CLUB" <[email protected]>
Sent: Monday, May 23, 2022 5:55:23 PM
Subject: Re: [CDV700CLUB] CDV-700 Transformer Tester and other essential shop-made service tools

Does anyone here have a manual for a Lectrotech Model TT-250 In-Circuit Transistor Analyzer?? I have one that seems to have issues, and do not understand how it is supposed to be used.? I have had no luck finding a manual or schematic.? Even finding someone that has a working one and/or knows how to use it properly would be good.? Here’s the most info I have found on it: ?? There are picture on eBay of one or more of them.? It does transistors and diodes.? Mine seems to have auto-biasing issues, and the leakage currents may be inaccurate.? High and low Beta ranges don’t line up well.? The in-circuit test mode seems to have problems due to switches that need to be cleaned, but does work for Beta Checks.? I will have to tear into it at some point, but it wasn’t a cheap tester in its day so I’d like to get it tuned up and 100% working as it seems to have a lot of potential.

I have been testing some Germanium transistors and getting “interesting” results with my Multi-Function Tester-TC1.? I’ll post the data after I get it all entered.

?

Clay Scott

?

From: [email protected] [mailto:[email protected]] On Behalf Of peter via groups.io
Sent: Monday, May 23, 2022 2:20 PM
To: [email protected]
Subject: Re: [CDV700CLUB] CDV-700 Transformer Tester and other essential shop-made service tools

?

geo

i have the same heathkit tr checker
it just a different colour. i got mine for $1 at ham club swap meet. i also have a radio shack tr tester that uses the transistor in an oscillator to light a neon bulb. it gives a crude relative gain estimate

p

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#690

开云体育

Does anyone here have a manual for a Lectrotech Model TT-250 In-Circuit Transistor Analyzer?? I have one that seems to have issues, and do not understand how it is supposed to be used.? I have had no luck finding a manual or schematic.? Even finding someone that has a working one and/or knows how to use it properly would be good.? Here’s the most info I have found on it: ?? There are picture on eBay of one or more of them.? It does transistors and diodes.? Mine seems to have auto-biasing issues, and the leakage currents may be inaccurate.? High and low Beta ranges don’t line up well.? The in-circuit test mode seems to have problems due to switches that need to be cleaned, but does work for Beta Checks.? I will have to tear into it at some point, but it wasn’t a cheap tester in its day so I’d like to get it tuned up and 100% working as it seems to have a lot of potential.

I have been testing some Germanium transistors and getting “interesting” results with my Multi-Function Tester-TC1.? I’ll post the data after I get it all entered.

?

Clay Scott

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of peter via groups.io
Sent: Monday, May 23, 2022 2:20 PM
To: [email protected]
Subject: Re: [CDV700CLUB] CDV-700 Transformer Tester and other essential shop-made service tools

?

geo

i have the same heathkit tr checker
it just a different colour. i got mine for $1 at ham club swap meet. i also have a radio shack tr tester that uses the transistor in an oscillator to light a neon bulb. it gives a crude relative gain estimate

p

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#689

geo

i have the same heathkit tr checker
it just a different colour. i got mine for $1 at ham club swap meet. i also have a radio shack tr tester that uses the transistor in an oscillator to light a neon bulb. it gives a crude relative gain estimate

p

Re: CDV-700 Transformer Tester and other essential shop-made service tools

#688

All transistor electronics in the late 50's and early 60's available to the general public, used germanium PNP transistor with rare exception. We didn't even have silicon rectifiers until much later in the 60's.
These circuits were always POSITIVE GROUND, as are the ENi CDV-700. This causes a lot of confusion to service technicians who were used to negative grounded tube circuits, since forever. I remember watching the Raytheon ads in the monthly trade magazines, showing the CK-722 glass, germanium transistor with prices, they were Expensive! finally when they came down to a dollar, I considered buying one but did not, as in those days the average salary was $1 per hour, and gasoline was 30cents per gallon.? A popular Earl Schieb TV ad said " I will paint ANY CAR for $29.95!".

At the surplus stores a WW2 ARC shortwave receiver set could be bought for $5, but an industrious youngster could fill his bicycle baskets with trash-canned old radios and TV sets all day long for nada. I can't say how many Muntz 5-tube wonder TV sets I scrapped for parts, unsoldering every resistor and capacitor, straightening their leads, sorting into small raisin boxes, and cigar boxes. boxes for storage and later use. every screw, terminal strip, switch, transformer and tube were likewise recycled into my preteen inventory.

Early automobile broadcast radios that proudly displayed "Transistorized", didn't necessarily mean all-transistor by any means. Those hybrid radios used starved-circuit vacuum tubes for most everything except audio, as the transistors of that day were low frequency devices. As technology quickly progress, more and more stages within radios became transistorized.

Germanium transistors are finicky and have unique failures that are not always easy to diagnose. Leakage is one of those issues.

This simple little tester is perfect for checking that parameter. If it shows leaky, twist its wires together* and scrap it. It also has uses in matching transistors or comparing two of the same part # for better gain ones, where that is important. The Leakage/Gain switch is spring loaded to the Leakage position, insuring the first / most important test is done the instant the transistor is plugged in. My unit was modified for external battery holder, it's not something you use everyday and forgotton internal batteries can leak.

Yes there are many complex/expensive transistor testers out there today, but they can be tedious, confusing and really allow simple common faults to slip by.

The IT-10 was what we had back in the day and it was all we needed, then and now, when working on CDV-700 era stuff.

Schematic attached.

Geo
Germanium Transistor Leakage Tester.jpg

Germanium Transistor Leakage Tester.jpg

Heathkit-IT-10-Schematic.pdf

CDV-700 Transformer Tester and other essential shop-made service tools

#687
Edited

Top row, left to right?
Battery current meter- 2 ranges 0-50mA and 0-500mA. Eni CDV-700 draws about 55mA, a single 100 or 200mA would be fine.
Bare, transformerless, Eni CDV-700 PCB, updated with critical parts replaced/restored (more on range switch rebuilding later)
Transistor leakage/Gain tester, built by moi about 55-60 years ago from a HealthKit. Today I would make it myself from scratch (circuit will be provided)

Second row L-R
Substitute original ENi CDV-700 transformer with 18" std. color coded PtFE wires Bk=1, Red=2 Org=3 Yel-4 Grn-5 Blu-6, sorry Violet stayed home (made this last night)
Substitute CDV-700 meter with 18" color coded wires
Universal bench I/O PCB test jig. Besides the soldering iron, this is my most used bench tool!

Details of these and other test items to follow in later posts

Geo

Cover_1.jpg

Re: Leni conversion #3

#686

Perfect logic! Always start with working ENi original, make cautious repairs before doing actual circuit changes, the LENi conversion.

You're right about the need for a working board before making major changes. Much of the LENi mod is simply changing out know failure prone existing original parts anyway.

Geo

Show quoted text

From: "Michael" <mtcooper01@...>
To: "CDV700CLUB" <[email protected]>
Sent: Tuesday, May 17, 2022 11:15:11 AM
Subject: Re: [CDV700CLUB] Leni conversion #3

Geo -? okay no battery tray in box.??

and by the way - this is still an ENI board, I have not started a LENi conversion on it. I wanted to confirm original functionality first.? I figured if it was working as an ENI, then I'd do the rather straightforward conversion to a LENi.? never got there.?

Re: Leni conversion #3

#685

Geo -? okay no battery tray in box.??

and by the way - this is still an ENI board, I have not started a LENi conversion on it. I wanted to confirm original functionality first.? I figured if it was working as an ENI, then I'd do the rather straightforward conversion to a LENi.? never got there.?

Re: Leni conversion #3

#684

hi Lenox, yes all parts are new including that cap.??

Re: Leni conversion #3

#683

Keep the battery box, I have one.

It will come in handy for you as a test tool in the future.

George?

Show quoted text

From: "Michael" <mtcooper01@...>
To: "CDV700CLUB" <[email protected]>
Sent: Tuesday, May 17, 2022 10:36:12 AM
Subject: Re: [CDV700CLUB] Leni conversion #3

okay.. I have to admit being curious myself.??

I will send you:??
- the ENI board with the current parts on it (all new except the switch and Module A)
- please ignore the soldering boo boos... these phenolic single sided board cannot take many soldering hits, as you probably well know. My plan was to clean up and jumper the lifted pads once I confirmed functionality.? ??
- I have one transistor (V3) tacked to the bottom solder side I was going to put it in its proper place if confirmed good.??
- because whoever built these original boards loved to crimp leads, I snipped off most of the original parts.? The original transformers have little stubs of leads left on them.? Still probeable.??
- the original transformer, and one of the ones I got off eBay, and the one Lenox had provided me is soldered on the board now (note the transformer is not yet secured to the board).??
- and since the battery cage is hard wired to the board, i will send it along attached as well, without batteries.? Oh - one of the battery cage negative through hole rings lifted - I was going to fix that as part of final clean up.? ?

Re: Leni conversion #3

#682

开云体育

?

That’s interesting.? The colors on the schematic that I sent worked for me.? I agree with Geo that there is something strange going on with that board.? I ended up replacing the high-voltage filter capacitor and that fixed things.? Have you tried that?

?

Lenox

?

Subject: Re: [CDV700CLUB] Leni conversion #3

?

Beam me up CDV1701A...?

okay...? update.? ?
1.? George - this ENI board is a mess.? Thanks for the offer to look at it, but I think I am sending it skyward as space junk.? ?
2.? Lenox had provided me a couple generic transformers two years ago, one of them salvaged a past LENi project.? I tried one on this ENI.?
there are two different instructions for the color coding of this transformer and matching the pinouts of CDV 700.??
a) color codes were hand written in pencil on the box the transformer came in.? I tried that hookup first -? description of results below. Basically - a steady hum from transformer, some HV but low.? Cannot hit 15V (5.7V). No sound out of speaker at all.??
b) Lenox provided a schematic with color codes hand written in at the transformer pins? I rewired yesterday to this pinout. Worse results.? I get HV, but, now has a dirty scratchy 'hum/buzz' from the board (not the speaker).? Definitely not a happy sound.? ?The 15V is now around 1V.? ?The meter does not move to position on the dial, nor, does it respond to check source.? No sound out of speaker at all.??

so ... as warping through space look out for the little ENI board zinging by.? ?

thanks
Michael C

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