Repairing HP Officejet R-series

HP Officejet R-series

HP Officejet R-series

As a fan of vintage tube equipment, it should come as no surprise that I prefer older quality computer equipment.  In this article, I explain how to repair “Scanner System Failure” problems in a vintage HP Officejet R-series multifunction scanner-printer.  Model R40xi is shown in the photos, but all models (R40, R40xi, R60, R60xi, R80, R80xi) repair the same.  In fact, many similar HP multifunction units of this era are repaired in similar manner.

First, let me explain why I feel that these vintage HP units are worth repairing.  Why fix an “old parallel-port printer” when new models are so cheap?  Like most things in life, you really do get what you pay for, and if HP paid me to take their new models (with the assumption that I actually had to use them), I would not be interested.

During the Lew Platt years, HP was making top quality products.  This period of quality was from the early 1990s (Laserjet 4-series and beyond) through the Officejet R-series of 1999.   The hardware during this time was built-like-a-tank, and when compared to today, the ink supplies were reasonable (although they certainly seemed expensive at the time).

Let us look at the economics: Officejet R-series uses a #45 cartridge, holds 42-mL ink, retail cost $30.  This HP45 can be purchased for $5 on eBay. Modern HP cartridges hold as little as 5-mL ink and cost $15 — which is 4.2 times more expensive using retail price comparisons.  If you consider surplus #45 cartridge prices as your comparison, the cost to operate a new HP printer can be  42-times more expensive.  And consider this — is it environmentally responsible to even manufacture an ink cartridge that only holds 5-mL or 10-mL? Certainly not, and is only done to make the cartridge price appear to be low cost.   That is an insult to your intelligence and an affront to the environment.

In another example, a modern HP toner cartridge (for a current model) costs $99 retail with approx 2,000 page yield.  Surplus HP toner cartridges for the old 4-series, 5-series, or 6-series can be purchased for approx $20-$30 on eBay, and have 3,000+ page yields.  Vintage Laserjets have been known to be run strong with 500,000 page cycles.  Any chance you would get even 50,000 page cycles with a modern unit?  And how many Nag messages from the new drivers to “buy more ink” would you click on during that time?  Well — no nag messages with old HP units!

So when you analyze the situation, the answer is obvious why I fix these old HP units.  (1) High build quality of the hardware, (2) low cost of use (ie – cheap ink), (3) OS drivers that respect you as a person, without bloat or nag screens to harass extra ink purchases, (4) ink that does not “expire” because some Executive wanted to sell more ink to pay for his/her 7-figure CEO salary+stock options+benefits+perks+Golden Parachute retirement package.

Let us compare the “new” models.  By ‘new’ models, I consider any model released in the Carly Fiorina era and beyond to be ‘new’.  The only benefits that I can see in the new models are USB connection (which is easier for most users but otherwise adds no functionality) and much better color printing.  Since I have no problem with parallel ports and only print black-and-white, those issues are not important to me. Otherwise, it is my opinion that the quality of the new hardware is much lower than the older models, the cost of consumables (ink/toner) is outrageously expensive, the computer drivers are bloated and filled with nag messages that harass you to “buy more ink”, and some models “expire” the ink cartridges based upon a random date.   If you feel respected as a customer with that experience, more power to you.   Personally, I am not interested in participating.

With that explanation, let us move on to the repair.  As always, repairs are only suited for experienced electronic technicians with suitable training.

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Testing panel meters

©2009, All rights reserved.

The article will discuss a cheap and easy way to test panel meters. The meter in your tube tester is an example of a panel meter. Occasionally you see flaky meter operation and suspect that the panel meter may be defective.  Most techs know that you cannot test a panel meter by placing a multimeter across its terminals — this attempt can ruin the panel meter and will not disclose the panel meter specs anyway.

Most panel meters in vintage equipment (such as tube testers or capacitor testers) will be milliammeters or microammeters.  The good news is that these panel meters can be tested, although extreme caution must be exercised.  One mistake and you can easily ruin the meter, so “do not try this at home” until you have practiced with a large variety of junk meters and have sufficient experience and confidence in your skills. Even then, “triple check” everything before you proceed.

Simpson 2600 Calibrator

Simpson 2600 Calibrator

Many people think that you need to have expensive equipment to test panel meters.  It would be nice to own a Simpson 2600 Laboratory-grade Calibrator (which cost $1,620 in 1965 and weighs 132-lbs).  But you can make do with the following basic equipment: a variable power supply, a quality resistor decade box that allows for individually switching in-and-out of circuit precision resistors, a quality ammeter (your ammeter must have microamp capability to test µA meters), and a quality digital multimeter.  Likewise, you need an understanding of what you are trying to accomplish and an ability to determine whether your panel meter is AC or DC.   Keep in mind that Ohm’s Law teaches that voltage, resistance, and current are all interrelated, therefore a panel meter that has its faceplate scale in “volts” CAN be tested as an ammeter.

In the following discussion, I will demonstrate testing three panel meters from different equipment.  In all three examples, the manuals/schematics/parts-lists do not provide the specs for the meter — the full scale range and internal resistance is unknown.  You are therefore evaluating the “unknown”, and your goal is to (1) determine the full-range specs of the meter, (2) evaluate whether the meter action is smooth and accurate across its entire range, and (3) determine the approximate internal resistance of the meter.

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Malibu will not start, disable Passlock II

A common (and totally random) problem with GM vehicles that have the Passlock / Passlock II anti-theft system is that the vehicle will suddenly refuse to start.  The problem is a poorly designed GM Passlock anti-theft system that erroneously enters anti-theft mode and disables the fuel injectors. GM should be forced to recall this Passlock system — it is simply unacceptable to strand motorists because of an incompetent anti-theft system.

The vehicle in this example is a 2002 Chevy Malibu, but this Passlock system was employed in many GM models.  Thousands of motorists have been stranded and left helpless by these GM vehicles that refuse to start for no apparent reason.  The owner of this Malibu was stranded three times over the past two years, incurred 2 towing bills to a Chevy dealership, two “repair” bills from the incompetent Chevy dealer who obviously failed to solve the problem.  Now she was stranded for a 3rd time.  This time she called me.

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Mercury Tube Testers

This article will discuss Mercury tube testers. The Mercury Electronics Corporation of Mineola NY produced a number of tube testers in the 1960s.  All models are small, portable, and lightweight.  Popular models include 990, 1000, 1100, 1100A, 1100C, 1101.  Models and comments will be added as I find time.   Electrical voltages are present; repairs should only be attempted by a qualified technician.

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Sencore Calibration Module for TC162-TC154

I am frequently asked to explain how to make or buy the Sencore Calibration Module for solid-state Mighty Mite models TC154 and TC162. Information to build and use the calibration module is provided in the Sencore Service Manual for each tester. There is no reason to buy a calibration module — it can be easily built by anyone with sufficient skills to repair and calibrate the tester.

I am providing the calibration module information below, but keep in mind that this is NOT a substitute to owning the service manual. One should not expect to properly service (let alone calibrate…) any piece of equipment without a service manual and schematic. Likewise, this sencore calibration module is NOT a magic bullet — you use this LAST — after you have thoroughly inspected and checked the tester circuitry.  Using the calibration module without performing full circuit inspection beforehand is quite senseless. ALL of the work is in the circuit testing and preparation. These testers are approx 40+ years old — you cannot assume that any component is still within tolerance. That said, here is the Calibration Module information.

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Solid state replacement for #83 tube

I am frequently asked by B&K and Hickok owners to explain how to replace a #83 tube with a solid state version. This question is popular because #83 tubes are scare and expensive. Other benefits are increased reliability (no tube to wear down), less heat generated inside the tester case, and less load on the power transformer. So, if you want to Do-It-Yourself, I will explain how these replacements are made.

I will preface this tutorial with a few caveats: First, this procedure is easier to implement with B&K testers than Hickok testers. Hickok factored in the load that the real #83 tube has on the power transformer, and sometimes you cannot properly set the line without circuit modification. Keep this in mind if you plan to try it with your Hickok — you may be getting in over your head. Hence, substitution may be more effort than it is worth, especially when some Hickok buyers do not want the modification and would have to undo the circuit mods that were made. This leads to the second caveat: not everyone feels that the solid-state substitution works ‘excellent’ in Hickok’s. In fact, some “purists” will not even use a Hickok with a solid-state #83 replacement. They cite the fact that silicon diodes have less voltage drop than a tube rectifier, and feel that the tube test results will not be “pure.”

Personally, I always use a solid-state replacement for B&K testers. For Hickok, I prefer to use a real #83 tube only because circuit modifications are sometimes necessary, which makes going back to a real #83 difficult for the tube tester owner or future buyer. That said, I have no disapproval with using a solid-state #83 in a Hickok, and have found that any tube “test score” differences are trivial. In my opinion, the people who argue about small test score variations are really over-thinking the purpose of testing a tube — the end-result is NOT a test score, but to ascertain whether the tube will work satisfactory in your circuit. Common sense and practicality are important.

Here it goes…

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New drivers for D-Link DWL-G122 Rev B

This article explains how I installed/updated Windows Vista® drivers for a D-Link® DWL-G122 Rev B USB network adapter. This article is informational-only and not intended as advice. Improper driver installation can cause your PC to crash, lockup, or fail to boot. Proceed at your own risk, and no ‘tech support’ is provided.

The article is only relevant to Revision B (known as B1) of this adapter (the DWL-G122 was available in 4 different revisions). The Rev B1 version was very popular because it had native Linux driver support, and also worked well with Windows XP. I have personally used the adapter under Linux (Suse® and Ubuntu®), XP, and Vista®. Unfortunately, D-Link has done a poor job of releasing new drivers for this adapter. To date, D-Link had only released one beta driver package for Vista 32 (Vista X86), and nothing for Vista 64. The Vista 32 beta driver is no longer available for download, either. Luckily, Rev B1 contains a Ralink® RT2500USB chipset, and Ralink has continuously updated the Windows drivers for this adapter. The latest driver package (as of this writing) is dated 11-11-2008, and contains drivers for Vista 32-bit, Vista 64-bit, XP 32/64.

Installing these drivers for D-Link DWL-G122 Rev B1 cannot be done conventionally, but the process is reasonably easy for any seasoned PC technician. To maintain a “clean” PC, I will extract the drivers in a Virtual Machine. This step is optional.

These are the steps that I performed to update the driver for Vista 32 (complete with screenshots):

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Repair & calibration NRI 70 Tube Tester

This article will discuss repair and calibration of the NRI Professional model 70 tube tester. High voltages are present, repairs should only be attempted by a qualified technician. Copyrighted, all rights reserved.

The exact tester that you see in the photos below is available for sale at $310 plus shipping.

NRI 70 beautiful hardwood case

NRI 70 beautiful hardwood case

Introduction

The high-quality craftsmanship of the NRI Professional model 70 tube tester is readily apparent. It has a beautiful hardwood case (appears to be oak or birch) with finger-joint construction. Eight rubber feet protect your desktop in both the working position and the standup position. Internally, the tester uses a large beefy transformer and quality Pace meter movement. The tester has very small size, measuring only 10.75 x 10.75 x 6.25 inches (27cm x 27cm x 16cm) and weighs a hefty 10.4 lbs (4.7 kg). Most of the weight is due to the large transformer and hardwood case.

The NRI 70 has eight built-in sockets consisting of 4-pin, 5-pin, 6-pin, 7-pin large, 7-pin miniature, octal, loctal, and 9-pin miniature. All sockets use standard wiring (1-to-1, 2-to-2, etc.), and the control lever numbers correspond to their RTMA pin numbers (Lever 1 controls socket pin 1, Lever 2 control socket pin 2, etc.) Read the rest of this entry »

1940 Jackson modernization bulletin

I recently found a February 1940 Jackson tube tester modernization bulletin. This bulletin explains the modernization options available for Jackson tube tester models 627, 627-C, 630, 633, 634, 634-C, 634-D, 635, 637, 680. It also includes the wiring diagram to install a Loctal socket into models 627, 630, 633, 635, 680.

Very interesting bulletin for anyone collecting or repairing vintage Jackson tube testers. I have scanned this 4-page document into a PDF for your benefit.

[ Download the Jackson 1940 Modernization Bulletin PDF ]

To summarize the bulletin:

  • Models 634 and 637 sold in 1940 were already modernized at the factory
  • Models 634 and 637 sold in their first year (1939) can be easily modernized by the owner (see my article on Jackson 634 for modernization data to install 9-pin miniature socket into these models).
  • Models 627, 630, 633, 635, and 680 could be sent back to the Jackson factory and modernized for $5.00 (model 633) or $6.50 (models 627, 630, and 635, which dated from 1938), or $12.50 (model 680). All five of these models had to modernized at the factory because they required installation of a supplementary high-voltage filament transformer, among other parts.
  • Models 427-A, 435-A, 535, and 580 were too obsolete to be modernized because “no provision for the high voltage filament types can be made. Miniature types cannot be tested.” Jackson noted that these models were “as much as five years old”, which dates them between 1935 and 1940. Jackson recommended upgrading to the new 1940 models of 634 and 637.

If you are only interested in the Loctal socket modernization wiring diagram, see the accompanying thumbnail photo (click photo to enlarge).

Jackson modernization diagram for adding a Loctal socket

Loctal socket modernization

For Sale – Sencore Mighty Mite meter

Going through my parts inventory, I found two nice Sencore Mighty Mite meters.

  • Meter for TC-130 Mighty Mite III
  • Meter for TC-136 Mighty Mite IV

Each is good condition, tested in-circuit and known to work good.

Price is $74 each plus Priority Mail (less than $5 to most USA destinations).

Email if interested. Again, these are meters – not the entire tester. If you need a replacement meter, this is your opportunity.