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← 300B
Rolling Candidates to replace 300B
Power Triode — DHT — UX4
⚠ Safety
Drop-In Replacements
✓
WE300B
✓
4300A
✓
4300B
✓
AV300B
✓
CV2609
✓
HF-300B
✓
PX300B
Top 10 Picks
71A
drop-in
5V
⚠ Low Pa
350A
adapter
5V
⚠ Low Pa
Rolling Candidates (20)
i
Heater:
2V
0
2.5V
0
4V
0
5V
0
●
6.3V
0
7V
0
7.5V
0
10V
4
11V
2
show all (9)
Fit:
Drop-in
0
Adapter
0
Status:
✓ Safe
6
⚠ Close, low Pa
2
⚠ Low Pa
12
0 shown (target 5V only)
▣ Compact
⚙ Thresholds filter
No candidates match the selected filters.
Show candidates on other heater voltages (8 additional)
Generated 2026-04-09
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