TSH-06F IC Tester — Vol 4: Beyond the TSH-06F

Testers that do RAM, standard TTL and open-collector parts properly, most of them under $100. What each can do that the TSH-06F cannot.

4.1 What the TSH-06F leaves on the table

Vols 2 and 3 set out where my tester stops:

No memory. It has no RAM tests at all. My Heathkit ET-3400 trainer uses 2112 static RAMs (256 words × 4 bits, 16-pin, socketed), and the TSH-06F can’t check them.
Standard-TTL quirks. Its library is built on 74LS/74HC numbers, so the standard 7451 and 7454 may be tested against the wrong pinout (Vol 3).
Open collector unknown. Nothing documents whether it pulls up open-collector outputs.
A fixed library. It has no port and no updates, and no user can add a part.
24 pins. Nothing bigger fits.

The research below looked for devices at hobby prices that close those gaps, read on 8 November 2026. Prices move, and several of these are small-batch projects, so check the links before buying.

4.2 The short list

Table 1 — The short list

Device	Rough price	Standalone?	RAM it tests	7451/7454 & open collector	Can be updated?
TSH-06F (mine)	about $45	Yes	None	Unverified	No
Retro Chip Tester Pro	€40–60 in parts; pre-built at cost from the designer	Yes (LCD, SD card)	2101, 2102, 2111, D2112A, 2114, 6116, 6264, 62256; DRAM 4116, 4164, 41256	Standard 7403, 7416, 7451 listed; open-collector method not stated	Yes (ISP)
XGecu T48 (or TL866II Plus)	about $55–100	No: USB, needs a PC	6116, 6264, 62256 only	Yes: separate 7451, 7454 and 74LS54 tests; open-collector tests check for “off”	Yes; open-source software with editable tests
IKCH-55 (Robert Krten)	not stated	USB console	2112 named	Functional only; can’t tell a 7404 from a 7405	Open design
Vintage RAM Tester V3	$37	Yes (OLED)	2114, 4116, 4164, 41256 and more, with real memory-test patterns	Logic: none	Yes; open source (GPLv3)
BackBit Chip Tester Pro	about $200	Yes	2111, 2114, 2147, 2148, 4104; 4116 with a ~$20 adapter	Logic library, MOS/Commodore-focused	Yes
1024-bit shift register tester	PCB + Arduino Nano	Yes	—	—	Open source (MIT); tests 2504/1404 shift registers

4.3 Retro Chip Tester Pro: the one that covers both of my jobs

Designed by Stephan Slabihoud at 8bit-museum.de, the Retro Chip Tester Professional (RCT) is the retro-computing community’s most-recommended tester. It is the most-recommended option in a Vintage Computer Federation thread on the subject (VCFed forum thread). It is an ATmega2560 board with a 32-pin ZIF, a 20×4 character LCD and an SD-card slot, and it runs without a PC (8bit-museum.de RCT page).

What it does that the TSH-06F doesn’t:

Static RAM. Its page lists 256×4 SRAMs “D2101A, D2111, D2112A…” among chips that “and all pin-compatible SRAMs can be tested”, plus the 2102, 2114, 6116, 6264 and 62256 (8bit-museum.de). The 2112 is listed as the D2112A and not marked as tested on a real chip. Check its pinout against an ET-3400 2112-2 before relying on it, but it is the nearest commercial fit.
Dynamic RAM. 4116, 4164 and 41256, among others, with no adapter mentioned for the 4116’s extra supplies.
Over 1,200 logic types, including standard-TTL numbers the TSH-06F lacks: 7403, 7416, 7442, 7451 and 7495 are in its list. The page doesn’t say how it handles open-collector outputs.
ROM and EPROM reading to the SD card, with a ROM-identification database.
Firmware updates over ISP. The design isn’t formally open source, but its schematics and parts list are published.

Getting one: it is mostly a build-it-yourself board. The designer puts the parts at €40–60 and offers a board “pre-assembled with the ATmega2560 at cost price” through the site’s contact form, with buy links at 8bit-museum.de/buy. One buyer’s write-up describes receiving bare boards and sourcing the parts himself (celso.io, July 2025). It also notes that complex chips such as the 6502 and 6522 are beyond it. A ready-built Tindie listing has been retired (Tindie, endresz_eu).

4.4 XGecu T48 / TL866II Plus: the cheap fix for the KENBAK-1 chips

These are EPROM/flash programmers with a 40-pin ZIF that also test logic chips, and they need a PC. The T48 is the current model, about £55 at a UK dealer (38-3D, XGecu T48) and around US $96 on eBay (eBay listing). XGecu’s own Xgpro software runs on Windows. The open-source minipro project drives these programmers from Linux, and its logic-test database is plain, editable XML (minipro on GitLab).

I read that database, logicic.xml, on 8 November 2026. It answers both of Vol 3’s KENBAK-1 traps:

7451 and 7454 have their own standard-TTL tests, separate from a 74LS54 test. A 7454 is tested against a 7454’s pinout, not the LS one.
Open-collector tests check for “off”. The 7403 entry expects a Z (high-impedance) output where a totem-pole gate would expect HIGH, and “7405@OC / 7406@OC” do the same. The 7416 is grouped with the 7404 under a totem-pole test that expects HIGH, so the safer way to test a 7416 is with the 7406@OC test (same pinout and function).
Every other KENBAK-1 type is there: 7400, 7408, 7410, 7420, 7430, 7442, 7474, 7486, 7495.

Its weaknesses:

Memory: for static RAM, the database covers only the 6116, 6264 and 62256. It has no 2112, 2114 or DRAM (minipro infoic.xml).
Logic list: Silicon Chip counted 226 logic parts and saw auto-detect misname a 74HC14 (Silicon Chip, Feb 2022).
Seating: EEVblog users report errors from chips seated off-centre in the ZIF (EEVblog forum).

Like the TSH-06F, it is a static vector test at 5 V, with no speed or drive measurement.

4.5 IKCH-55: a DIY tester that names the 2112

Robert Krten’s IKCH-55 uses two Raspberry Pi Picos behind a 40-pin ZIF at 3.3 V or 5 V, with a USB serial console. It covers 7400 to 74688 and the 4000 series, and lists the 2112 “256 x 4 static RAM” by name, the only design found that does (krten.com IKCH-55). Krten is candid that it is “certainly not an exhaustive full-spec electrical test”, and that it can’t tell a 74LS04 from a 74LS05. So it doesn’t check open-collector outputs. Price and availability aren’t stated.

4.6 Vintage RAM Tester V3: a proper memory test

The TSH-06F and the programmers check whether a chip responds. A memory tester checks every cell. The Vintage RAM Tester V3 from tops4u (US $37 on Tindie) runs March C- on static RAM, along with checkerboard, address-line and data-retention tests. It also works the refresh on DRAM, and a 4164 takes 1.8 seconds. It covers the 2114, 4027, 4116 (on-board −5 V and +12 V), 4164, 41256, 4416, 4464 and 514256, but not the 2112 (Tindie listing; open source at github.com/tops4u/Ram-Tester).

4.7 BackBit Chip Tester Pro

About $200. It is strong on MOS and Commodore support chips, and tests the 2111, 2114, 2147, 2148 and 4104 SRAMs, plus the 4116 with an optional tri-voltage adapter of about $20 (Oasis BBS review; Applefritter thread). No 2112. In that thread, a regular warns that its go/no-go tests are not parametric.

4.8 Testing the KENBAK-1’s 1404A memories

No commercial tester found handles the Intel 1404A. One open-source Arduino Nano project tests 1024-bit dynamic shift registers, listing the Signetics 2504, “1404” and AMD AM2804. It was built for Apple-1 replica builders, whose video memory uses the same family. It is MIT-licensed, with schematic and PCB files (GitHub, renatasdgt; PCBWay project). The 1404A isn’t named, and the text doesn’t describe how it makes the clock swings and negative supply. Read its schematic against Intel’s 1404A data sheet before trusting a result. It is still the only way found to check the two spare 1404As before they go into the machine.

4.9 The professional end, for scale

ABI ChipMaster Compact Pro: 40 pins, about £610–820 new, and memory needs a separate RamMaster (Rapid Electronics).
B&K 575A: discontinued, used units only. It covers TTL, CMOS, memory and interface chips, with adjustable thresholds, a real parametric step the hobby testers lack (Global Test Supply).
GW Instek GUT-6600A: discontinued, $600 list, 14–24 pins, TTL and CMOS logic (GW Instek).

Even these are mostly functional testers. In the VCFed thread above, one user passes on a friend’s verdict that the ChipMaster “can’t be fully trusted”. For a stubborn chip, the machine it lives in is still the final test.

4.10 Where this leaves my bench

Table 2 — Where this leaves my bench

Job	Best tool found	Notes
KENBAK-1 TTL, first screen	TSH-06F	Calibrated on known-good chips (Vol 3)
KENBAK-1 7451, 7454, 7403, 7416	XGecu T48 + minipro, or a breadboard	Proper standard-TTL and open-collector tests
ET-3400 2112 RAMs	Retro Chip Tester Pro, or the IKCH-55	Confirm 2112-2 pin compatibility first
KENBAK-1 1404A spares	The 1024-bit shift-register tester (DIY)	Check its clocking against the 1404A sheet
Full DRAM/SRAM cell test	Vintage RAM Tester V3	2114 and DRAM, not the 2112

4.11 Building a better one

None of these testers measures anything electrical, and none handles the odd early memories well. The DIY IC Tester dive asks what a tester designed for vintage parts would look like. It starts with a stopgap that tests 2112 RAMs on an XGecu T48, and goes on to a from-scratch board.