Restoration Shop

This is the Restoration Shop, where new life is breathed into classic electronic equipment.

In creating the Amptech Systems service and restoration facilities, my goal was to approximate and improve upon the layout and equipment complement of a well-equipped television and electronics service facility circa mid 1960's.  Equipped with instruments which were widely available new and as military surplus at the time, I now have all equipment necessary for servicing a range of sets from late-1920's (early AC powered) radios to 1960's (round CRT) color televisions.  Additional equipment will be arriving soon which will increase shop efficiency and allow shorter lead times by simplifying the setup of 1940's-vintage b/w televisions which use a different Intermediate Frequency than was used in later b/w models and color sets.  Many modern devices such as tv, vcr, hi-fi and guitar amplification systems may also be serviced using these facilities.

This is the Schematic Library where classic Service Literature is kept.

This is the Display Room featuring my personal collection of working vintage sets.

Purchasing a Set

Many of my sets are sold on eBay.  Click this link to visit my eBay

member page and view my Current Auctions list.

Restoration Services

We have begun further expansion of our capabilities.  Beginning in February, 2009, we expect to have two complete multi-station restoration shops available to meet the needs of our clients.  During the same month when conventional TV undergoes its full transformation to Digital, we at Amptech Systems reaffirm our dedication to the historic preservation of sets from the early years of the Analog Age.   

 Online Restoration Request Form

Parts Inquiries

Hobbyists and Do-It-Yourself restorers in need of parts or tubes may click here to obtain parts vendor referrals free of charge.  We will research your request and reply with a referral to one or more vendors who may have the requested part available for sale, usually within 24-48 hours.  Type numbers are typically sufficient for identifying tubes.  Manufacturer's part numbers, type numbers and other characteristics are helpful for other parts.  Pictures are helpful for identifying unusual parts.  We typically keep only frequently-used replacement parts on hand for use in restorations, ordering other parts as needed from a number of outside vendors specializing in New, New-Old-Stock, and/or Used  vintage and hard-to-find electronic parts. 

Send an email requesting parts research

This service is provided free of charge, however, donations are appreciated from those who have found our vendor referrals helpful. 

Other Related Inquiries

General information regarding vintage electronics is available free of charge.  See our Hobbyists' Page first for some topics which we have addressed recently.

Send an email requesting other information

Cabinetry Service Inquiries

Ask our Cabinetry Specialist about Cabinet work (Finishes, Decals, etc.) for Vintage TV, Radio, Phonograph and other related wood cabinetry. 

Send an email requesting information about Cabinetry work

Recent Restorations

Click the images for more information and pictures

Repair and Restoration of Antique and Vintage Radio, TV and Musical products.

Key Benefits

Warranty Details

Warranty covers Labor performed as part of a Restoration.  Parts actually replaced during the restoration process may also include a warranty, such warrantees are dependent upon and administered by the manufacturers of those components.  Generally, only NEW vacuum tubes by current-production tube manufacturers will feature factory warranties.

An email must be received prior to the Warranty Expiration Date printed on the Service Invoice to initiate a Warranty claim.  Removal of the set's back cover, unless specifically instructed to do so, will void the Warranty.  Specific instructions will be given for any situation requiring removal of a tube, fuse, or other access to the inside of the set to resolve a technical issue.  Please provide a detailed description of any observed malfunction.

Shipping damage claims shall be handled by the shipping service provider.  Shipping insurance is MANDATORY on all completed restorations which are to be shipped upon completion.  Shipping damage is NOT a Warranty issue and shipping providers WILL be billed for the consultation services of Amptech Systems at Tutorial rate for any research we are called upon to perform as part of damage claim resolution.     

Technical Support

As part of the Labor Warranty on completed Restorations, Technical Support on the restored set is provided free of charge.  Email service@amptechsystems.com for details.  Out-of-warranty technical support is billed at Tutorial rate.

Capabilities

Your antique and vintage electronics will be repaired or restored by an expert technician using quality materials and 25 years' experience with vintage electronics including design, construction, troubleshooting and repair.

Quality Standards 

The Restoration Process

Initial Cleaning and Inspection

All restorations begin with careful study of the service manual for the device.  The equipment to be restored is cleaned to allow a thorough and accurate inspection.  The chassis is removed from the cabinet, carefully dusted and vacuumed.  After the chassis and components are cleaned, all components are inspected to spot obvious signs of component failure.  Such indications as cracks, breakage, melting or burning of components are noted for further investigation.  Any severely damaged parts are noted for immediate replacement.  All tubes (including tv picture tubes) are individually tested using an appropriate tube tester.

Modern Overload Protection

Many vintage sets had inadequate overload-protection provisions.  Some had no such protection at all.  We add fuses to protect the set's AC line circuit, main B+ supply, and television horizontal deflection circuits.  We use special subminiature fuse devices which are easily concealed under the chassis, often using existing terminal lugs as connection points.  Wherever possible, we use vacant terminals of tube sockets after consulting engineering data for the specific type of tube as many tubes' unused pins may be used as "tie points" for other components unless otherwise noted in the engineering data.  Use of tube socket "vacancies" in this manner also facilitates testing of the fuses without removing the chassis from the cabinet when a blown fuse is suspected.  External appearance of the set is not modified unless a client specifically requests a user-accessible line fuse installation.  Protective devices are specifically selected to minimize the risk that some future failure of a tube or other component could initiate "chain-reaction" damage affecting other parts for which replacements may be expensive or hard to find.  

Electrolytic Capacitor Re-Forming

In the previous steps, electrolytic capacitors were inspected for signs of pressure or blow-out at their safety seals. which are clear indications of previous failure.  Capacitors which have already failed were noted for replacement.  Those which do not show signs of failure will have their internal aluminum oxide dielectric film re-formed using a controlled electrochemical process.  After re-forming is complete, the capacitors are tested for correct performance.  Tests include ESR (Equivalent Series Resistance), DC Leakage, and Capacitance/Tolerance.  By testing ALL THREE of the key indicators for proper electrolytic capacitor performance, we maintain optimum set operation, maintain original appearance, and eliminate unnecessary replacement of these components.  New-manufacture multi-section aluminum electrolytics may be available (from one of our preferred vendors) in some instances where replacement is required.  We have also just completed development of an improved process for concealing new electrolytic capacitors inside the existing metal cans in instances where the original capacitors have actually failed, must be replaced, and our vendor does not carry a suitable replacement for the unit(s) to be replaced.  This process eliminates re-engineering of under-chassis wiring and avoids blocking access to critical test points which could occur when new electrolytics are installed under the chassis in the conventional manner.  Future maintenance is less difficult with our improved method.  Rebuilt units will be fitted with a Rebuilt By Amptech Systems label showing the date when the rebuild was performed.

Circuit Resistance Check

Service manuals typically contain charts showing normal resistance measurements between individual tube pin connections and the set's "ground" point.  Measurements are taken in this step for comparison to the service manual's chart of normal values.  Differences of greater than 10%-20% are noted, investigated and corrected.

Electronic Functional Evaluation

In this step, the chassis is connected to an antenna and variable power source and an ammeter is inserted in the main supply circuit.  DC voltmeters are connected to measure the main B+ and B- power sources.  For television sets, a 0-40kV voltmeter is attached to measure the high-voltage output and a 5" or 8" test picture tube is connected to the set.  A dual-trace oscilloscope is also available for waveform analysis later in this step.  Input voltage is gradually increased toward 100% until rated line current or rated B+ and B- voltage readings are observed.  If excessive current is observed, the problem is investigated and corrected.  If proper supply voltages are attained with normal supply current, key waveforms are analyzed with the oscilloscope.  Normally, the screen of the test picture tube will show illumination at this point and the speaker will indicate proper operation of the set's audio amplifier.  During this test, 90%-95% of television chassis will produce a picture on the screen of the test picture tube.

RF/IF Response Test 

Most sets' service manuals specify a procedure for a general response check of the set's Radio Frequency and Intermediate Frequency circuits.  In this step, the results of the test are compared with figures shown in the manual.  Incorrect results are investigated and corrected as necessary.  Full system alignment is performed if test results indicate a need for it or if the customer requests re-alignment.

Recapping

This step is normally optional and performed only if it is deemed necessary or upon special request of the customer.  By this phase in the procedure, all failed and/or failing components have been replaced;  normal operation of all circuits has been restored; and no further work is necessary.  Purely from a standpoint of preventive maintenance, customers may request replacement of components for which there is no immediate need for replacement.  Most vintage television chassis contain 20 to 40 paper-dielectric capacitors which show a high rate of failure when the chassis has been stored in an environment of high humidity.  If previous tests have resulted in replacement of more than approximately 30% of these parts to achieve normal operation, the set's remaining paper-dielectric capacitors may be replaced with new Mylar-dielectric units for preventive purposes.  About 15 aluminum electrolytic capacitors are used in the typical vintage television chassis as individual units or combined in multi-section devices.  If more than 30% of these have needed replacement to achieve normal operation, replacement of all aluminum electrolytic capacitors may be an appropriate preventive measure.  A report of the set's test results will be completed and a summary of the results and recommendations will be furnished (usually via email) to the customer upon completion of each phase of restoration.

Here is our latest development.  We now have the capability of rebuilding multi-section can-type electrolytic capacitors of the "twist-lock" type.  We open the can, remove the inner structures, rebuild with new electrolytics, and finally re-seal the can.  This is a labor-intensive process performed only on units having at least one section which has failed any of the three tests which we perform on every electrolytic capacitor in the sets we restore and for which no New or New-Old-Stock direct replacement unit is available.  We prefer, when available, to use fresh-stock CE Manufacturing capacitors, NOS capacitors from other vendors if there is no current-production CE Manufacturing unit suitable for the application, and rebuilding is our next option for those "don't have and can't get" types.  All components to be used in our rebuilds are pre-tested and then re-tested after assembly.  Each phase of testing is the same three-step testing which the original capacitors had undergone.  The rebuilt capacitor section being post-tested below, rated 40uF with original tolerance of -10%/+20%, is well within tolerance at 47.3uF.  Leakage current measured a full 33% below maximum acceptable value at 10% above rated voltage, and ESR measured less than 1 ohm. 

Final Adjustments and Burn-In

After all required and recommended procedures have been performed and satisfactory operation of the chassis has been verified, the set is fully reassembled and set up in the shop.  Its final adjustments are performed and the set is subjected to a burn-in period.  During this phase, I watch several hours of off-air programming and videotaped test patterns on the set to further confirm correct and reliable performance. 

Billing

The results and recommendations from each step have been submitted to the customer at each phase of the restoration process.  A minimum and maximum cost estimate has accompanied each reporting summary.  Final cost of restoration is calculated and an invoice is generated for final billing.  Due to the complex nature of the systems under test and work being performed, diagnostic charges may apply even if the process is aborted due to preliminary cost estimates' exceeding the maximum approved by the customer.  The maximum diagnostic charge will be within +/-10% of the minimum cost estimate specified in the most-recent reporting summary and represents the time and materials involved to this point.  Typical diagnostic and reporting charges are $50 to $100.  Completed restorations typically bill as the average of the most-recent minimum and maximum cost estimate +/-10%.  Typical charges for completed functional restoration are $150-$500.  Special procedures such as recapping and cabinet refinishing may result in final charges of $500-$1,000.    Return shipping charges also apply unless the set is to be picked up personally at my shop.

Special Note (TV Picture Tubes)

TV Picture Tubes are very hard to find. We do not normally have access to any new ones. We have, however, found providers of rebuild service for most all-glass and some metal-and-glass picture tubes.  This service is very expensive, however, and recommended only under special circumstances. A rebuilt picture tube will add at least $300 to final restoration cost.  In most cases, the cathode of a weak tube may be electrically re-activated to achieve satisfactory performance for normal light-duty operation of the set for demonstrations.  Monthly demonstrations of 1-2 hours duration are recommended and re-activated tubes normally continue to function for several years under these conditions before rebuilding or replacement becomes necessary.   Occasionally, a suitable used tube may be obtained for a fraction of the cost of rebuilding the tube.  As of 09/23/2009, a used 10BP4 (1940's-vintage round B/W) tube costs about $150. For some 1950's-vintage rectangular B/W tubes, New Old Stock replacements are available on a limited basis from a local warehouse.  Picture tubes MUST be intact and under vacuum in order for our rebuilding vendor to successfully complete the rebuilding process.  If your set's CRT is broken or otherwise obviously not under vacuum, a rebuildable replacement tube must be obtained.

Send an email requesting rebuildable replacement CRT price quote 

Send mail to webmaster@amptechsystems.com with questions or comments about this web site.

Last modified: 07/08/09