Choosing calibration equipment standards can feel like two completely different shopping trips. At one extreme is a vintage null indicator sold as-is; at the other, a field-grade pressure calibrator. The decision comes down to what you need to calibrate: a temperature indicator, a bridge circuit, or a pressure gauge in a process loop.
Quick Take
If you need a pressure calibrator and your budget sits in the middle of this group, the used Fluke 719 30G is a practical path. At the top of the range, the Fluke 719Pro 300G is described in great working and cosmetic condition. On a very tight budget, the B&K 750 is the cheapest way into a null indicator, but it is sold as-is. The Thermo Electric 311600 is the repair-project option for someone who wants a temperature calibrator/indicator for parts or refurbishment.
Price Comparison
| Product | Listed Price | Price Bar | What It Does |
|---|---|---|---|
| B&K 750 Test Equipment Calibrator Null Indicator | POWERS ON UNTESTED | USD 49.00 | Vintage null indicator, powers on, untested | |
| Thermo Electric 311600 Temperature Calibrator Indicator Digi-Mite [A1B1 | USD 98.50 | Temperature indicator/calibrator, for parts or not working | |
| Fluke 719 30G Electric Pressure Calibrator 12 - 30 psi 719-30G | USD 1,200.00 | Pressure calibrator, -12 to 30 psi | |
| Fluke 719Pro 300G Electric Pressure Calibrator 719Pro-300G 719 Pro | USD 2,999.99 | Pressure calibrator, 300G model designation |
Decision Matrix
- Need a powered vintage null indicator on a minimal budget? Choose the B&K 750, with the understanding that only the power-on function has been confirmed.
- Need a temperature calibrator/indicator as a repair or parts donor? The Thermo Electric 311600 is the one to consider.
- Need a working pressure calibrator without jumping to the top price? The Fluke 719 30G fits low-pressure calibration work.
- Need the 300G model designation from Fluke and can accept the top price? The Fluke 719Pro 300G is the serious option.
Product Notes
Thermo Electric 311600 Digi-Mite
Sold for parts or not working, the Thermo Electric 311600 comes from a closed plant's parts crib and is being sold without a bench check. If you have experience troubleshooting temperature indicators, this could yield a working bench calibrator at USD 98.50. The "Digi-Mite" name points to a digital temperature indicator/calibrator, and the unit carries a China country of origin. The clear limitation: it's a gamble. You are paying for a board and housing that may only be useful for components. Choose it only if a repair project is part of the plan.
B&K 750 Test Equipment Calibrator Null Indicator
Priced below the others at USD 49.00, the B&K 750 is used, wired, and blue. It is described as powering on when plugged in, with no other checks performed. That makes it a reasonable starting point for someone who already has test gear and wants a null indicator for bridge or potentiometer work. Scratches and age are part of the deal, and the unit is sold strictly as-is. Expect cosmetic wear and an untested condition. If your budget is nearly zero and you can verify the rest of the circuit yourself, this is the cheapest way into a powered vintage calibrator.
Fluke 719 30G Electric Pressure Calibrator
For an actual working pressure calibrator without climbing to the top price, the Fluke 719 30G is listed at USD 1,200.00 and covers -12 to 30 psi. That price puts it between the budget vintage units and the top-price Fluke. That range makes it a direct fit for low-pressure process loops, pneumatic controls, and similar tasks. It is described as a high-quality tool for precise calibration. The limitation is range: if your application exceeds 30 psi, this unit will not cover it. Buy it when 30 psi is enough and you want a dedicated pressure calibrator.
Fluke 719Pro 300G Electric Pressure Calibrator
At USD 2,999.99, the Fluke 719Pro 300G is the most expensive calibrator in this group. This used unit is described as in great working and cosmetic condition, pulled from the field due to an upgrade, and sold as calibrator only. That means you are getting the calibrator itself, with only what is pictured. It is a used unit, but the described condition is a major step up from the B&K and the parts-only Thermo. Choose it when you need the 300G model designation and your budget supports a serious investment.
Final Recommendation by Use Case
- Choose the B&K 750 if you need an inexpensive, powered null indicator for vintage bench work and are comfortable troubleshooting unchecked functions.
- Choose the Thermo Electric 311600 if you want a temperature calibrator/indicator as a repair or parts donor.
- Choose the Fluke 719 30G if you need a usable pressure calibrator in a low-pressure range and want to stay well under the top price.
- Choose the Fluke 719Pro 300G if you need that model designation, the described condition matters to you, and your budget allows the top price in this comparison.
